JPWO2003042103A1 - Surface-treated calcium carbonate, method for producing the same, and resin composition containing the calcium carbonate - Google Patents

Abstract

It consists of calcium carbonate surface-treated with an organic surface treatment agent. It has a specific BET specific surface area (Sw), a heat loss per unit specific surface area (As), and a specific pore distribution by the mercury intrusion method. The maximum average pore diameter (Dxp) and the average pore diameter [maximum value of mercury intrusion increase (Dyp) / average pore diameter (Dxp)] are satisfied. A substance that forms a complex is added to a calcium hydroxide slurry, carbon dioxide is blown to synthesize calcium carbonate, the calcium carbonate concentration is adjusted and aged, and the surface treatment is performed with an organic surface treatment agent. In particular, it is useful for resins, and when blended in a resin, it is possible to improve the adhesive force between the resin composition and the adherend and to form a tough coating film.

Description

本発明に用いられる炭酸カルシウムの好ましい製造方法を以下に具体的に説明する。
（反応条件）
▲１▼の石灰乳濃度は、３．５〜１０．２重量％が好ましい。石灰乳濃度が３．５％未満の場合、生産性が低くコスト高になるばかりでなく、これ以上濃度を薄めても分散性の向上は期待しにくい。一方、１０．２重量％を越えると、反応後の一次粒子径の凝集が起きやすく、熟成を行っても平均二次粒子径より大きめになり、所望の粘度物性が得られにくい。従って、より好ましくは５．０〜９．０重量％、更に好ましくは６．０〜８．０重量％である。
▲２▼の錯体形成物質の添加量は、０．５〜１５重量％が好ましい。添加量が０．５重量％未満の場合、本発明の目的とする微粒子が得られにくく、一方、１５重量％を越えると、反応後の１次粒子が細か過ぎるため、熟成後の二次粒子径が好ましい分散状態である（ｆ）式の範囲を満たない場合があり、結果的に所望の高粘度付与が得られにくい。添加時期においては、炭酸化反応前、炭酸化反応途中のいずれでもよく、反応前と反応途中の両方で添加してもよい。
錯体形成物質としては、クエン酸、シュウ酸、リンゴ酸等のヒドロキシカルボン酸とそのアルカリ金属塩、アルカリ土類金属塩及びアンモニウム塩；グルコン酸、酒石酸等のポリヒドロキシカルボン酸とそのアルカリ金属塩、アルカリ土類金属塩及びアンモニウム塩；イミノジ酢酸、エチレンジアミン４酢酸、ニトリロトリ酢酸等のアミノポリカルボンとそのアルカリ金属塩、アルカリ土類金属塩及びアンモニウム塩；ヘキサメタ燐酸、トリポリ燐酸等のポリ酢酸とそのアルカリ金属塩、アルカリ土類金属塩及びアンモニウム塩；アセチルアセトン、アセト酢酸メチル、アセト酢酸アリル等のケトン類；硫酸とそのアルカリ金属塩、アルカリ土類金属塩及びアンモニウム塩等が挙げられ、単独であるいは２種類以上組み合わせて使用することも可能である。中でもヒドロキカルボン酸類は、カルシウムとの結合性が高く、特にクエン酸は好適に使用することができる。
▲３▼の炭酸ガス流量としては、水酸化カルシウム１Ｋｇ当たり、通常３００〜３０００Ｌ／ｈｒである。３００Ｌ／ｈｒ未満では、反応後の１次粒子が大きくなりやすく、３０００Ｌ／ｈｒを越えると工業的にコスト高になり好ましくない。
▲４▼のガス濃度に関しては、１０〜５０％が好ましい。ガス濃度が１０％未満の場合、反応後の１次粒子が大きくなりやすく、５０％を越えると工業的にコスト高になり好ましくない。
（熟成条件）
▲５▼の炭酸カルシウム濃度に関しては、２．４〜１３．０重量％が好ましい。２．４重量％未満の場合、工業的に生産性が低く、一方、１３．０重量％を越えると、熟成により分散性が向上し系の構造粘性が上昇した場合に、系を均一に撹拌することができにくくなり、平均２次粒子径が（ｆ）式の範囲を満たない場合がある。結果的に、所望の高粘性付与が得られにくくなる。従って、より好ましくは４．０〜１１．０重量％、更に好ましくは５．０〜９．０重量％である。
上記したように、熟成濃度は分散性を向上させるための重要な指標になりやすいため、微少な粒子ほど濃度を好ましい範囲に薄くした方がより効果的である。
▲６▼の熟成時間に関しては、分散性の指標として好ましい範囲である（ｆ）式を満足するレベルまで熟成を行えば、本発明の目的である高粘性付与の発現が得られやすいので好ましい。従って、上記の製造条件により熟成時間が左右されるため、熟成時間は特に限定されるものでないが、通常２４〜２４０時間が好適である。熟成時間が２４時間未満の場合、所望の分散した粒子が得られにくく、２４０時間を越えると工業的にコスト高となる。従って、より好ましくは３０〜２００時間、更に好ましくは４０〜１８０時間である。
上記以外の製造条件は、従来の常法通りに行えばよい。例えば、合成温度条件は通常５〜３０℃の範囲であり、熟成温度条件は通常３０〜７０℃の範囲である。また、熟成時の撹拌条件も、液系全体が均一に撹拌できる程度の撹拌力であれば十分であるが、従来の撹拌能力であると、やむおえず系の濃度を薄める必要性が生じコスト高になりやすい。生産性はもちろんのこと分散性を向上させる点においても、撹拌能力は従来より高い方が好ましい。尚、撹拌機構もパドル、タービン、プロペラ、高速インペラ等が一般的に用いられる。
（表面処理）
▲７▼の表面処理量に関しては、炭酸カルシウム生地の比表面積によって左右されるため、式（ｂ）のＡｓの範囲内であれば特に限定されるものでないが、通常３．５〜５０重量％である。表面処理量が３．５重量％未満の場合、本発明の微細で高分散性である炭酸カルシウムの表面を十分に覆うことができない場合がある。この結果、乾燥・粉末化の際、未処理面同士で２次凝集を形成するため、該表面処理炭酸カルシウムとしての効果が十分発揮できにくくなる。一方、５０重量％を越えると、表面処理剤過多による樹脂成分あるいは可塑成分への遊離がおこり、ブリード現象や表面肌荒れ現象の原因となりやすい。従って、より好ましくは５〜４０重量％、更に好ましくは７〜３５重量％である。表面処理方法は特に限定されず、湿式、乾式のいずれでもよい。
本発明で用いられる有機系表面処理剤は、カプリル酸、ラウリン酸、ミリスチン酸、パルミチン酸、ステアリン酸、アラギン酸に代表される飽和脂肪酸、オレイン酸、エライジン酸、リノール酸、リシノール酸に代表される不飽和脂肪酸、ナフテン酸に代表される脂環族カルボン酸、アビエチン酸、ピマル酸、パラストリン酸、ネオアビエチン酸に代表される樹脂酸及びこれらの不均化ロジン、水添ロジン、２量体ロジン、３量体ロジンに代表される変成ロジン、アルキルベンゼンスルホン酸に代表されるスルホン酸類およびそれらのアルカリ金属塩、アルカリ土類金属塩、アンモニウム塩、アミン塩、さらには次に例示されるアニオン性、カチオン性、ノニオン性の界面活性剤を単独であるいは２種類以上組み合わせて使用することも可能である。とりわけ、脂肪酸のアルカリ金属塩、樹脂酸のアルカリ金属塩が炭酸カルシウムとの吸着反応性の点で好ましい。
アニオン性の界面活性剤としては、ポリオキシエチレンアルキルエーテル硫酸等で例示されるアルキルエーテル硫酸、ポリオキシエチレンアルキルエーテル燐酸等で例示されるアルキルエーテル燐酸、ポリオキシエチレンアルキルフェニルエーテル硫酸等で例示されるアルキルアリールエーテル硫酸、ポリオキシエチレンアルキルフェニルエーテル燐酸等で例示されるアルキルアリールエーテル燐酸、ポリオキシアルキル硫酸エステル等で例示されるアルキル硫酸エステル、ポリオキシアルキル燐酸エステル等で例示されるアルキル燐酸エステル、ポリオキシアルキルフェニル硫酸エステル等で例示されるアルキルアリール硫酸エステル、ポリオキシアルキルフェニル燐酸エステル等で例示されるアルキルアリール燐酸エステル、脂肪酸アルキロールアミドの硫酸エステル等で例示されるアルキルアミド硫酸エステル、ポリオキシエチレンアルキルスルホン酸等で例示されるアルキルスルホン酸、アルキルベンゼンスルホン酸、アルキルナフタレンスルホン酸、スルホコハク酸、ジアルキルスルホコハク酸エステル等で例示されるスルホコハク酸エステル、α−オレフインスルホン酸、Ｎ−アシルスルホン酸及び／又はそれらのアルカリ金属、アルカリ土類金属塩、アミン塩、アンモニウム塩等のアニオン性界面活性剤、α、β不飽和モノカルボン酸、α、β不飽和ジカルボン酸、メタアクリル酸アルキルエステル、アルコキシ基を有する（メタ）アクリルエーテル、シクロヘキシル基を有する（メタ）アクリレート、α、βモノエチレン性不飽和ヒドロキシエステル、ポリアルキレングリコールモノ（メタ）アクリレート、ビニルエステル、ビニル系芳香族、不飽和ニトリル、不飽和ジカルボン酸エステル、ビニルエーテル、共役ジエン、鎖状オレフイン、環状オレフイン、スルホ基含有単量体等からなる共重合物等で例示されるアニオン性高分子分散剤及びそれらのアルカリ金属、アルカリ土類金属、アンモニウム等による部分もしくは完全中和された塩等があげられる。
また、カチオン性の界面活性剤としては、ステアリルアミンアセテート、ステアリルアミン塩酸塩などの脂肪族アミン塩、ラウリルトリメチルアンモニウムクロライド、ステアリルトリメチルアンモニウムクロライドなどの脂肪族４級アンモニウム塩、アルキルベンジルジメチルアンモニウムクロライドなどの芳香族４級アンモニウム塩、複素環４級アンモニウム物等のカチオン性界面活性剤、アミノ基（第１アミン基）、イミノ基（第２アミン基）、第３アミン基、第４アンモニウム基、ヒドラジノ基等の極性基を有するカチオン性高分子系分散剤、それらの極性基を有する単量体と共重合可能な単量体、例えばα、β不飽和モノカルボン酸、α、β不飽和ジカルボン酸、メタアクリル酸アルキルエステル、アルコキシ基を有する（メタ）アクリルエーテル、シクロヘキシル基を有する（メタ）アクリレート、α、βモノエチレン性不飽和ヒドロキシエステル、ポリアルキレングリコールモノ（メタ）アクリレート、ビニルエステル、ビニル系芳香族、不飽和ニトリル、不飽和ジカルボン酸エステル、ビニルエーテル、共役ジエン、鎖状オレフイン、環状オレフイン、スルホ基含有単量体等の単量体との共重合物及びそれらのアルカリ金属、アルカリ土類金属、アンモニウム等により部分もしくは完全中和された塩等が例としてあげられる。
さらに、ノニオン性の界面活性剤としては、ポリオキシエチレン及びその誘導体、カルボキシベタイン、スルホベタイン等で例示されるベタイン、アミノカルボン酸、イミダゾリン誘導体が例としてあげられる。
表面処理後、前記した（ｆ）式を満たすたようスラリー中に含まれるアルカリ金属イオン等の夾雑イオンをろ過水洗することが望ましい。また、ろ液の電気伝導度は特に限定されないが、通常１０ｍＳ／ｃｍ以下、より好ましくは１ｍＳ／ｃｍ以下、更に好ましくは３００μＳ／ｃｍ以下である。
水洗方法に関しては特に制限はなく、シックナー、オリバー、ロータリーフィルター、ラロックスプレス等を用い、水洗・濃縮を行うことができる。
上記の如き、本発明の表面処理炭酸カルシウムは、特に樹脂用に好適であり、例えば、成型用樹脂、塗料用樹脂、インキ用樹脂、シーラント用樹脂、接着剤用樹脂等各種の樹脂に配合され、優れた特性、物性を有する樹脂組成物とされる。
成型用樹脂としては、特に制限されるものではないが、例えばＡＢＳ樹脂、フッ素樹脂、ポリエチレンテレフタレート、ポリカーボネート、ポリエチレン、ポリプロピレン、エチレン−プロピレン共重合体、エチレン又はプロピレンと他のモノマーの共重合体等のポリオレフィン系樹脂、ポリスチレン系樹脂、アクリル系樹脂、メタクリル系樹脂、塩化ビニル系樹脂、塩化ビニリデン系樹脂、ポリアミド系樹脂、ポリエーテル系樹脂、酢酸ビニル系樹脂、ポリビニルアルコール系樹脂等に代表される熱可塑性樹脂や、フェノール樹脂、ユリア樹脂、メラミン樹脂、エポキシ樹脂、ポリウレタン樹脂、ポリイミド樹脂等に代表される熱硬化性樹脂を例示することができ、これらの樹脂成分は単独又は２種類以上組み合わせて使用される。
本発明の表面処理炭酸カルシウムとこれらの樹脂との配合割合は特に限定されず、所望の物性に応じて適宜決定すればよいが、通常、樹脂１００重量部に対して表面処理炭酸カルシウム１〜１００重量部が好ましい。必要に応じ、安定剤等の各種添加剤を添加しても良いことは勿論である。
塗料用樹脂としては、特に限定されるものではないが、アルキド樹脂、アクリル樹脂、酢酸ビニル樹脂、ウレタン樹脂、シリコーン樹脂、フッ素樹脂、スチレン樹脂、メラミン樹脂、エポキシ樹脂等に代表される溶剤系塗料用樹脂、水系塗料においては、アルキド樹脂、アクリル樹脂、ラッテクス樹脂、酢酸ビニル樹脂、ウレタン樹脂、シリコーン樹脂、フッ素樹脂、スチレン樹脂、メラミン樹脂、エポキシ樹脂等に代表される一般塗料用エマルジョン樹脂、アルキド樹脂、アミン樹脂、スチレン−アリルアルコール樹脂、アミノアルキド樹脂、ポリブタジエン樹脂等に代表される一般塗料用水溶性樹脂、エマルジョン樹脂と水溶性樹脂とをブレンドした塗料用ディスパージョン樹脂、架橋型水可溶性樹脂を乳化剤としたディスパージョン樹脂、アクリルハイドロゾル等を例示することができ、これらの樹脂成分は単独又は２種類以上組み合わせて使用される。
本発明の表面処理炭酸カルシウムとこれらの樹脂との配合割合は特に限定されず、所望の物性に応じて適宜決定すればよいが、通常、樹脂１００重量部に対して表面処理炭酸カルシウム１〜１００重量部が好ましい。必要に応じ、可塑剤、分散剤等の各種添加剤を添加しても良いことは勿論である。
プラスチゾル用樹脂としては、塩化ビニルゾル、アクリルゾル、水溶性アクリルゾル、ウレタンゾル等を例示することができ、これらの樹脂成分は単独又は２種類以上組み合わせて使用される。
本発明の表面処理炭酸カルシウムとこれらの樹脂との配合割合は特に限定されず、所望の物性に応じて適宜決定すればよいが、通常、樹脂１００重量部に対して表面処理炭酸カルシウム１〜１００重量部が好ましい。必要に応じ、安定剤等の各種添加剤を添加しても良いことは勿論である。
インキ用樹脂としては特に限定されるものではないが、ロジン変成フェノール樹脂、尿素樹脂、メラミン樹脂、ケトン樹脂、ポリ塩化ビニル樹脂、ポリ塩化ビニル−酢酸ビニル共重合体、ブチラール樹脂、スチレン−マレイン酸樹脂、塩素化ポリプロピレン、アクリル樹脂、クマロン・インデン樹脂、石油樹脂、ポリエステル樹脂、アルキド樹脂、ポリアミド樹脂、エポキシ樹脂、ポリウレタン樹脂、ニトロセルロース、エチルセルロース、エチルヒドロキシセルロース、環化ゴム、塩化ゴム等を例示することができ、これらの樹脂成分は単独又は２種類以上組み合わせて使用される。
本発明の表面処理炭酸カルシウムとこれらの樹脂との配合割合は特に限定されず、所望の物性に応じて適宜決定すればよいが、通常、樹脂１００重量部に対して表面処理炭酸カルシウム１〜１００重量部が好ましい。必要に応じ、安定剤、ドライヤ等の各種添加剤を添加しても良いことは勿論である。
シーラント用樹脂としては特に限定されるものではないが、ポリウレタン樹脂、ポリサルファイド樹脂、シリコーン樹脂、変成シリコーン樹脂、ポリイソブチレン樹脂、エポキシ樹脂、ポリエステル樹脂等を例示することができ、これらの樹脂成分は単独又は２種類以上組み合わせて使用される。
本発明の表面処理炭酸カルシウムとこれらの樹脂との配合割合は特に限定されず、所望の物性に応じて適宜決定すればよいが、通常、樹脂１００重量部に対して表面処理炭酸カルシウム１〜１００重量部が好ましい。必要に応じ、着色剤、安定剤等の各種添加剤を添加しても良いことは勿論である。
接着剤用樹脂としては特に限定されるものではないが、ユリア樹脂、フェノール樹脂、エポキシ樹脂、シリコーン樹脂、アクリル樹脂、ポリウレタン樹脂、ポリエステル樹脂等を例示することができ、これらの樹脂成分は単独又は２種類以上組み合わせて使用される。
本発明の表面処理炭酸カルシウムとこれらの樹脂との配合割合は特に限定されず、所望の物性に応じて適宜決定すればよいが、通常、樹脂１００重量部に対して表面処理炭酸カルシウム１〜１００重量部が好ましい。必要に応じ、安定剤、可塑剤等の各種添加剤を添加しても良いことは勿論である。
本発明の樹脂組成物には、本発明の表面処理炭酸カルシウム以外に、粘性、その他の物性を調整するために、コロイド炭酸カルシウム、重質炭酸カルシウム、コロイド状シリカ、タルク、カオリン、ゼオライト、樹脂バルーン、ガラスバルーン等の充填剤、ジオクチルフタレート、ジブチルフタレート等の可塑剤、トルエン、キシレン等の石油系溶剤、アセトン、メチルエチルケトン等のケトン類、セロソルブアセテート等のエーテルエステル等に例示される溶剤、或いはシリコーンオイル、脂肪酸エステル変成シリコーンオイル等、その他必要に応じて種々の添加剤、着色剤等を１種又は２種以上組み合わせて添加することが可能である。
本発明の樹脂組成物は、例えばシーラント、接着剤に代表される硬化型樹脂組成物の場合には、優れた粘性・チキソ性、並びに目地追従性を有する。また、例えば塗料、インキ用樹脂組成物の場合は、優れた防タレ性、高光沢、高い透明性、高い塗膜強度を有する。更に、例えば成形用樹脂組成物の場合は、ウエルドライン面の強度低下が防止され、優れた強度を有する。
以下に実施例及び比較例を挙げて本発明をより詳細に説明するが、本発明は、その要旨を越えない限り、これらに何ら制限されるものではない。
尚、以下の記載において、特に断らない限り、％は重量％、部は重量部を意味する。
実施例１
温度１０℃、濃度８％の石灰乳に、錯体形成物質としてクエン酸を水酸化カルシウムに対し１．７％添加し、該スラリーに水酸化カルシウム１ｋｇ当たり１７００Ｌ／ｈｒの２０％ＣＯ_２ガスを導入し、炭酸カルシウムスラリーを作製した。次いで該炭酸カルシウムスラリーを、濃度１０％に調整し、温度４５〜５０℃で５０時間撹拌熟成を行った。熟成後の平均粒子径（Ｄｘ）＝０．２０μｍであった。該炭酸カルシウムスラリーに、温水に熱溶解させた１０％ステアリン酸ナトリウムを炭酸カルシウム固形分に対して１５％添加し、撹拌することにより該表面処理剤を炭酸カルシウム表面に十分吸着せしめた後、脱水、乾燥、粉末化し、ＢＥＴ比表面積（Ｓｗ）＝４８ｍ^２／ｇの有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。尚、該表面処理炭酸カルシウムの２００℃〜５００℃の熱減量率（Ｔｇ）＝１１８ｍｇ／ｇであった。また、平均細孔直径（Ｄｘｐ）＝０．０１６μｍ、平均細孔径量（Ｄｙｐ／Ｄｘｐ）＝７９であった。得られた表面処理炭酸カルシウムの各物性値を表１に示す。
実施例２
炭酸カルシウムスラリー濃度を７％に変更した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表１に示す。
実施例３
熟成時間を１２０時間に変更した以外は、実施例２と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表１に示す。
実施例４
表面処理後にフィルタープレス機（ラロックス社製）を用い、ろ液の伝導度が３００μＳ／ｃｍまで炭酸カルシウムケーキを水洗脱水した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表１に示す。
実施例５
表面処理量を２５％に変更した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表１に示す。
実施例６
温度１０℃、濃度５％の石灰乳に、錯体形成物質としてクエン酸を水酸化カルシウムに対し１０％添加し、該スラリーに水酸化カルシウム１ｋｇ当たり１７００Ｌ／ｈｒの２０％ＣＯ_２ガスを導入し、炭酸カルシウムスラリーを作製した。次いで該炭酸カルシウムスラリーを、濃度３％に調整し、温度４５〜５０℃で１５０時間撹拌熟成を行った。熟成後の平均粒子径（Ｄｘ）＝０．３８μｍであった。該炭酸カルシウムスラリーに、温水に熱溶解させた１０％ステアリン酸ナトリウムを炭酸カルシウム固形分に対して３５％添加し、撹拌することにより該表面処理剤を炭酸カルシウム表面に十分吸着せしめた後、脱水、乾燥、粉末化し、ＢＥＴ比表面積（Ｓｗ）＝１２５ｍ^２／ｇの有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。尚、該表面処理炭酸カルシウムの２００℃〜５００℃の熱減量率（Ｔｇ）＝２９６ｍｇ／ｇであった。また、平均細孔径（Ｄｘｐ）＝０．００５μｍ、平均細孔径量（Ｄｙｐ／Ｄｘｐ）＝１４８であった。得られた表面処理炭酸カルシウムの各物性値を表１に示す。
実施例７
錯体形成物質として、クエン酸三ナトリウムを水酸化カルシウムに対し３％添加する以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表１に示す。
実施例８
有機系表面処理剤をラウリン酸に変更した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表１に示す。
実施例９
有機系表面処理剤をラウリン酸ナトリウムに変更した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
実施例１０
有機系表面処理剤をパルミチン酸ナトリウムに変更した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
実施例１１
有機系表面処理剤を、ステアリン酸ナトリウム：樹脂酸カリウム＝３：２に変更した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
実施例１２
有機系表面処理剤を樹脂酸カリウムに変更した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
実施例１３
有機系表面処理剤を、ステアリン酸ナトリウム：アルキルベンゼンスルホン酸ナトリウム＝３：１に変更した以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
比較例１
有機系表面処理剤の添加量を５％にした以外は、実施例１と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
比較例２
温度１０℃、濃度４％の石灰乳に、錯体形成物質としてクエン酸を水酸化カルシウムに対し１８％添加し、該スラリーに水酸化カルシウム１ｋｇ当たり１７０００Ｌ／ｈｒの２０％ＣＯ_２ガスを導入し、炭酸カルシウムスラリーを作製した。次いで該炭酸カルシウムスラリーを、濃度２％に調整し、温度４５〜５０℃で２００時間撹拌熟成を行った。熟成後の平均粒子径（Ｄｘ）＝２．３μｍであった。該炭酸カルシウムスラリーに、温水に熱溶解させた１０％ステアリン酸ナトリウムを炭酸カルシウム固形分に対して４５％添加し、撹拌することにより該表面処理剤を炭酸カルシウム表面に十分吸着せしめた後、脱水、乾燥、粉末化し、ＢＥＴ比表面積（Ｓｗ）＝１７５ｍ^２／ｇの有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。尚、該表面処理炭酸カルシウムの２００℃〜５００℃の熱減量率（Ｔｇ）＝４０２ｍｇ／ｇであった。また、平均細孔直径（Ｄｘｐ）＝０．００３μｍ、平均細孔径量（Ｄｙｐ／Ｄｘｐ）＝４７であった。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
比較例３
特開平１０−７２２１５号公報の実施例１の如く、温度１０℃、濃度１１．８％の石灰乳に、錯体形成物質としてクエン酸三ナトリウムを水酸化カルシウムに対し３％添加し、該スラリーに水酸化カルシウム１ｋｇ当たり１７００Ｌ／ｈｒの２０％ＣＯ_２ガスを導入し、炭酸カルシウムスラリーを作製した。次いで該炭酸カルシウムスラリーを、濃度調整を行わず炭酸カルシウム濃度１４．９％のまま、温度４５〜５０℃で５０間撹拌熟成を行った。熟成後の平均粒子径（Ｄｘ）＝０．５０μｍであった。該炭酸カルシウムスラリーに、温水に熱溶解させた１０％ステアリン酸ナトリウムを炭酸カルシウム固形分に対して１５％添加し、強撹拌することにより該表面処理剤を炭酸カルシウム表面に十分吸着せしめた後、脱水、乾燥、粉末化し、ＢＥＴ比表面積（Ｓｗ）＝４２ｍ^２／ｇの有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。尚、該表面処理炭酸カルシウムの２００℃〜５００℃の熱減量率（Ｔｇ）＝１０１ｍｇ／ｇであった。また、また、平均細孔径（Ｄｘｐ）＝０．０１８ｍ、平均細孔径量（Ｄｙｐ／Ｄｘｐ）＝２７であった。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
比較例４
温度１０℃、濃度１１．８％の石灰乳に、錯体形成物質としてクエン酸を水酸化カルシウムに対し０．２％添加し、該スラリーに水酸化カルシウム１ｋｇ当たり１７００Ｌ／ｈｒの２０％ＣＯ_２ガスを導入し、炭酸カルシウムを作製した。次いで該炭酸カルシウムスラリーを、濃度調整を行わず炭酸カルシウム濃度１４．９％のまま、温度４５〜５０℃で５０間撹拌熟成を行った。熟成後の平均粒子径（Ｄｘ）＝０．４９μｍであった。該炭酸カルシウムスラリーに、温水に熱溶解させた１０％ステアリン酸ナトリウムを炭酸カルシウム固形分に対して５％添加し、強撹拌することにより該表面処理剤を炭酸カルシウム表面に十分吸着せしめた後、脱水、乾燥、粉末化し、ＢＥＴ比表面積（Ｓｗ）＝１７ｍ^２／ｇの有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。尚、該表面処理炭酸カルシウムの２００℃〜５００℃の熱減量率（Ｔｇ）＝４２ｍｇ／ｇであった。
また、平均細孔径（Ｄｘｐ）＝０．０４２ｍ、平均細孔径量（Ｄｙｐ／Ｄｘｐ）＝３８であった。得られた表面処理炭酸カルシウムの各物性値を表２に示す。
比較例５
有機系表面処理剤を、樹脂酸カリウムに変更した以外は、比較例３と同様の製造方法で有機系表面処理剤を表面処理してなる炭酸カルシウムを合成した。得られた表面処理炭酸カルシウムの各物性値を表２に示す。

実施例１４〜２０、比較例６〜９
前記実施例１〜７、比較例１〜４で合成した表面処理炭酸カルシウムを用い、下記の配合に基づき成型用樹脂組成物を調製した。得られた成型樹脂組成物の評価結果を表３に示す。
（配合）
表面処理炭酸カルシウム １５部
ポリプロピレン樹脂 ８５部
上記の２種をヘンシェルミキサー（カワタ社製）にてドライブレンドした後、押出し成形機（神戸製鋼社製ＮＥＸＴ Ｔ−６０）でペレット化した後、射出成形機によりダンベル片を作製し、引張強度、曲げ弾性率、衝撃強度を試験した。但し、ウエルドライン面の強度測定の試験片については、２カ所のゲートから注入し、真ん中でウエルドライン界面を作った。その他の物性測定の試験片は１カ所のゲートから注入した。
得られた試験片について下記の方法で各種特性を測定、評価した。
（引張強度、曲げ強度、衝撃強度）
引張強度はＪＩＳ Ｋ７１１３のプラスチックの引張試験方法に、曲げ強度はＪＩＳ Ｋ７２０３の硬質プラスチックの曲げ試験方法に、衝撃強度についてはＪＩＳ Ｋ７１１１の硬質プラスチックのシャルピー衝撃試験方法にそれぞれ準じて行った。
（引っ掻き試験）
３０ｍｍ×８０ｍｍ厚さ１ｍｍに成形したプラスチック板を、引っ掻き試験機（東洋精機製作所社製）を用いて引っ掻き試験を行い、その状態を下記の基準で評価した。
◎：極めて良好（全く傷が付かない。）
○：良好（ほとんど傷が付かない。）
△：普通（多少傷が付く。）
×：不良（かなり傷が付く。）

表３の結果から明らかな様に、本発明の表面処理炭酸カルシウムを配合してなる成型用樹脂組成物は、引張強度、曲げ強度、衝撃強度に優れているだけでなく、ウエルドライン面の強度低下防止にも優れており、このことから被接着物との接着力にも優れていることもわかる。また、従来よりも炭酸カルシウムの添加量を５％程減量化でき、軽量化においても有効であることが確かめられた。
実施例２１〜２７、比較例１０〜１３
前記実施例１〜７、比較例１〜４で合成した表面処理炭酸カルシウムを用い、下記の配合に基づき塗料樹脂組成物を調製した。
（配合）

上記配合物を、粒ゲージにて２０ミクロン以下になるまでＳＧミルにて分散させた後、ガラスビーズを取り除いて塗料樹脂組成物を作製し、下記の方法で各種特性を測定、評価した。結果を表４に示す。
（光沢、耐水性試験後光沢、光沢保持率）
各塗料樹脂組成物をガラス板に１００ミクロンのアプリケーターを用いて片面に塗布し、常温にて２４時間乾燥後、村上式グロスメーターにて６０°光沢を測定した。その後、ガラス板を水中に浸漬し、３日後の光沢保持率を測定した。
（タレ性）
各塗料樹脂組成物をＫＵ値が７８になるようにミネラルスピリットを用いて希釈調整し、２５０、２００、１５０、１００ミクロンのアプリケーターを用いて、全黒測定用紙に塗布し、塗布後直ちに塗布面が垂直になるように立てかけ常温にて２４時間放置し、そのタレの状態を下記の基準で評価した。
○：良好（全くタレていない。）
△：普通（若干たれている。）
×：不良（タレている。）
（塗膜の引っ掻き試験）
各塗料樹脂組成物をガラス板に１０００ミクロンのアプリケーターを用いて片面に塗布し、常温にて１週間乾燥後、引っ掻き試験機（東洋精機製作所社製）を用いて引っ掻き試験を行い、その状態を下記の基準で評価した。
◎：極めて良好（全く傷が付かない。）
○：良好（ほとんど傷が付かない。）
△：普通（多少傷が付く。）
×：不良（かなり傷が付く。）

表４の結果から明らかなように、本発明の表面処理炭酸カルシウムを配合してなる塗料樹脂組成物は、防タレ性に優れていることから、高いチキソ性を有しており、且つ、耐水性試験後の光沢保持率に優れており、このことから、高耐久性及び、強固な塗膜強度を有することがわかる。
実施例２８〜３４、比較例１４〜１７
前記実施例１〜７、比較例１〜４で合成した表面処理炭酸カルシウムを用い、下記の配合に基づき調整したプラスチゾル樹脂組成物を調製した。
（配合）
表面処理炭酸カルシウム ３００部
アクリルレジン ゼオンアクリルレジンＦ３４５（新第一塩ビ工業
社製） ２５０部
ブロックウレタン樹脂硬化剤（三井武田ケミカル社製）１２０部
ＤＩＮＰ ５００部
ターペン ８０部
ウレタン硬化剤（三井武田ケミカル社製） ６部
それぞれ配合剤５Ｌ万能攪拌機（ダルトン社製）にて常温でツブが無くなるまで混練し、アクリルゾル樹脂組成物を作製し、下記の方法で各種特性を測定評価した。結果を表５に示す。
（粘性・チキソ性）
前記配合に基づき調整したアクリルゾルの粘度をＢＨ型粘度計を用いて２ｒｐｍ、２０ｒｐｍの粘度を測定し、２ｒｐｍ粘度／２０ｒｐｍ粘度をチキソ性として表示した。
（耐チッピング性）
電着塗装版に上記乾燥条件にて焼き付け硬化後の塗膜を、塗装面を上にして水平より６０°の角度で固定し、この塗膜面に垂直に立てた長さ２ｍのパイプの下端を当てＪＩＳナット落下試験法に準じてＭ−４ナットを落下させ、塗装面が破壊され下地が露出するまでのナットの積算重量で耐チッピング性を表した。

表５の結果から明かなように、本発明の表面処理してなる炭酸カルシウムを配合してなるプラスチゾル樹脂組成物は、粘性や強度（耐チッピング性）が明らかに改善されていることが確認された。
実施例３５〜４６、比較例１８〜２１
前記実施例１〜１１及び１３、比較例１〜４で合成した表面処理炭酸カルシウムを用い、下記の配合に基づき調整し、得られた硬化樹脂組成物の各種特性を評価した。結果を表６、７に示す。
（配合）
（基材）

それぞれの配合物を５リットル万能混合撹拌機（ダルトン社製）にて、ツブがなくなるまで十分混練し、基材および硬化剤を作製し、下記の方法で各種特性を測定評価した。結果を表６に示す。
（粘性・チキソ性）
前記配合に基づき調整した硬化樹脂組成物の基材粘度をＢＳ型粘度計を用いて１ｒｐｍ、１０ｒｐｍの粘度を測定し、１ｒｐｍ粘度／１０ｒｐｍ粘度をチキソ性として表示した。
（貯蔵安定性試験）
前記硬化樹脂組成物を恒温装置２０℃×２週間静置後の基剤粘度を測定した。
（Ｈ型引張強度及び伸び試験）
基材：硬化剤＝１０：１で十分に脱泡混合後、ＪＩＳ Ａ５７５７ ６．１１引張応力及び伸び試験に基づいてＨ型を作製し評価を行った。
（接着性試験）
上記Ｈ型引張強度試験において、下記の基準により接着性を評価した。
○：良好（材料破壊している。）
△：普通（やや界面剥離しているが、材料破壊もしている。）
×：不良（界面剥離している。）
（追従性試験後Ｈ型引張試験及び接着性試験）
上記Ｈ型引張強度試験において、５０％伸ばした状態で硬化物を１週間固定した後、同様にしてＨ型引張強度（残留応力）を測定し、また接着性を評価することにより、シーリング材の目地に対する追従性を評価した。

表６及び表７の結果から明らかなように、本発明の表面処理してなる炭酸カルシウムを配合してなる、シーラント、接着剤に代表される硬化樹脂組成物は、破断強度が高く、被着体との接着力に優れており、追従性試験後においてもその効果が維持されていることが確認できた。
また、実施例４及び８の如く炭酸カルシウム中のアルカリ金属含有量を水洗により低減することにより、貯蔵安定性が優れていることが確認された。
実施例４７、比較例２２
前記の実施例１２、比較例５で合成した表面処理炭酸カルシウムを用い、下記の配合に基づきインキ樹脂組成物を調製した。得られたインキ樹脂組成物の評価結果を表８に示す。
（配合）
表面処理炭酸カルシウム ２５部
ロジン変成フェノール樹脂 ３５部
アマニ油 ２０部
精製軽油 １７部
ドライヤー ３部
上記配合物を、粒ゲージで５ミクロン以下になるまで、３本ロール（井上製作所製）を用いて分散させ、インキ樹脂組成物を作製した。
（粘性・チキソ性）
上記配合に基づき調整したインキ樹脂組成物をＢＳ型粘度計を用いて１ｒｐｍ、１０ｒｐｍの粘度を測定し、１ｒｐｍ粘度／１０ｒｐｍ粘度をチキソ性として表示した。
（透明性）
上記配合に基づき調整したインキ樹脂組成物をガラス板に２５ミクロンのアプリケーターを用いて片面に塗布し、常温にて２４時間乾燥後、光電分光光度計（島津製作所社製）を用いて、５５０μｍ光透過率を測定した。
（光沢）
上記と同様にインキ樹脂組成物を塗布し、常温にて２４時間乾燥後、村上式グロスメーターにて６０°光沢を測定した。
（耐摩擦性試験）
各樹脂組成物を全黒測定用紙に２５ミクロンのアプリケーターを用いて片面に塗布し、常温にて２４時間乾燥後、ＪＩＳＫ５７０１の耐摩擦性試験に基づいて、Ｓ型摩耗試験機（サザーランドラボテスター）を用いて下記の基準で評価を行った。
○：良好（摩耗しない。）
△：普通（やや摩耗する。）
×：不良（かなり摩耗する。）
（接着性）
上記と同様に塗布乾燥後、セロテープ（登録商標）〔ニチバン社製ＣＴ４０５Ａ−１８〕を塗膜表面に張り付け、これを急速に引き剥がし、インキの剥離状態を下記の基準で評価した。
◎：極めて良好（全く剥離しない。）
○：良好（ほとんど剥離しない。）
△：普通（やや剥離する。）
×：不良（かなり剥離する。）
（耐引っ掻き性）
上記と同様に塗布乾燥後、引っ掻き試験機（東洋精機製作所社製）を用いて引っ掻き試験を行い、その状態を下記の基準で評価した。
◎：極めて良好（全く傷が付かない。）
○：良好（ほとんど傷が付かない。）
△：普通（やや傷が付く。）
×：不良（かなり傷が付く。）

表８の結果から明らかなように、本発明の表面処理炭酸カルシウムを配合してなるインキ樹脂組成物は、粘性・チキソ性付与効果に優れるだけでなく、光沢、透明性が高いことがわかる。更に、耐摩耗性、耐引っ掻き性に優れ、高い塗膜強度に優れており、被着体との接着性にも優れていることがわかる。その結果、従来よりも炭酸カルシウムの添加量を減量化することが可能となるため、インキ特性の安定化に有効である。
産業上の利用可能性
叙上の通り、本発明の有機系表面処理剤を表面処理してなる、特定の粒度特性を有する炭酸カルシウムは、特に樹脂用として有用で、樹脂に配合した場合に該樹脂組成物と被着体との接着力を向上させ、且つ強靱な塗膜を形成することが可能である。
本発明の表面処理炭酸カルシウムを、例えば成型用樹脂に使用した場合には、ウエルドライン面の強度低下を防止し、また、優れた衝撃強度を有する樹脂組成物を、例えば塗料、インキに使用した場合には、高光沢及び優れた防タレ性、高い塗膜強度を有する樹脂組成物を、例えばプラスチゾル用樹脂組成物に使用した場合には、優れた粘性・チキソ性及び耐チッピング性を有する樹脂組成物を、例えばシーラントや接着剤に代表される硬化型樹脂に使用した場合には、優れた粘性・チキソ性及び目地追従性を有する樹脂組成物を提供することができる。TECHNICAL FIELD The present invention relates to calcium carbonate obtained by surface-treating an organic surface treatment agent, a method for producing the same, and a resin composition obtained by blending the calcium carbonate, and more specifically, for example, represented by a sealant and an adhesive. When used in a curable resin, it gives a resin composition with excellent jointing ability as well as viscosity and thixotropic properties. For example, when blended with paints, inks, and plastisols, it has high gloss and high thixotropy. Calcium carbonate obtained by surface-treating an organic surface treatment agent, giving a resin composition that not only has sagging resistance but also realizes a high-strength coating film, its production method, and a composition thereof It relates to a resin composition.
BACKGROUND ART Calcium carbonate is widely used as a filler or pigment for plastics, paints, inks, sealants, adhesives, paper, rubber and the like. For example, sealants are widely used for waterproofing, sealing, etc. in the fields of construction, automobiles, flooring, etc., but are often applied to vertical parts, and of course, from construction to curing. It is necessary not to sag, and it is necessary to have high viscosity and high thixotropy.
In order to cope with the above problems, the present inventors have already proposed a method for producing precipitated calcium carbonate (Japanese Patent Laid-Open No. 10-72215). It has become to.
For example, the demand for siding boards is increasing rapidly in private homes, and siding boards are used with low modulus sealants in consideration of wet and dry wrapping and movement of components, but siding boards expand and contract under the influence of temperature and humidity. For this reason, the sealant needs to follow the joint. Conventionally, colloidal calcium carbonate has been used to give these characteristics, lowering the modulus after curing, increasing the followability to the adherend to some extent, and fine adjustment of the viscosity is possible, but further lower modulus In addition, the conventional colloidal calcium carbonate is the limit for viscosity adjustment by addition of a trace amount, and a finer and highly dispersible one is desired.
In paints and inks, colloidal calcium carbonate has been used for a long time. As for paints, in recent years, a guarantee period such as a 10-year guarantee has been set, and paints with higher durability have been demanded. Ink also has a problem that the transparency of the ink is lowered due to the difference in refractive index between calcium carbonate and the ink vehicle, so there is a demand to reduce the amount of conventional colloidal calcium carbonate and maintain the ink characteristics. Has been made.
Furthermore, in plastics, wollastonite and acicular calcium carbonate are used to prevent a decrease in the strength of the weld line of the injection molding machine, both of which have a relatively large particle size of several tens to 200 microns. There is a problem in that the impact strength is reduced. With conventional colloidal calcium carbonate, it has been difficult to suppress a decrease in weld line strength and impact strength.
In addition, vinyl chloride resin-based plastisol is often used especially for automobile bodies, but in recent years, alternatives to acrylic resin-based materials have been studied from the environmental viewpoint. In particular, in the acrylic resin system, thinning is being considered from the price difference with the vinyl chloride resin system as well as weight reduction, and a filler capable of imparting high viscosity with a small amount of addition is required. Colloidal calcium carbonate is not satisfactory.
In view of the actual situation, the present invention, when used in, for example, a curable resin typified by a sealant or an adhesive, has not only the effect of imparting viscosity and thixotropy but also a joint followability, such as paints, inks, and plastisols. When used in a plastic, it has high gloss, excellent sagging resistance, and high coating film strength.For example, when used in plastic, it prevents the weld line surface from being reduced in strength and has excellent impact strength. Calcium carbonate obtained by surface-treating an organic surface treatment agent capable of reducing the weight by reducing the amount added to the resin, a method for producing the same, and a composition thereof The resin composition obtained is provided.
As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention added a specific substance to perform a carbonation reaction, and then aged at a specific concentration. Precipitated calcium carbonate with good properties, surface treatment of the calcium carbonate with a specific amount of organic surface treatment agent improves the adhesion to the adherend, and the strength of the formed coating film itself As a result, the inventors have found that these problems can be solved and completed the present invention.
DISCLOSURE OF THE INVENTION That is, the first of the present invention is characterized in that calcium carbonate surface-treated with an organic surface treatment agent satisfies the following formulas (a), (b), (c) and (d): The content of the surface treated calcium carbonate is as follows.
(A) 20 ≦ Sw ≦ 200 (m ² / g)
(B) 1.0 ≦ As ≦ 7.5 (mg / m ² )
(C) 0.003 ≦ Dxp ≦ 0.03 (μm)
(D) 50 ≦ Dyp / Dxp ≦ 180
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
AS: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxp: In the mercury intrusion method, in the pore distribution in the pore range of 0.001 to 0.1 μm, the mercury intrusion increase amount (integrated pore volume increase amount / log average pore diameter) is the maximum value (Dys). Average pore diameter (μm)
Dyp: Maximum value of mercury intrusion increase (mg / l)
Dyp / Dxp: Average pore diameter The second aspect of the present invention is that calcium carbonate surface-treated with an organic surface treatment agent satisfies the following formulas (a), (b), (e) and (f): The content of the surface-treated calcium carbonate is as follows.
(A) 20 ≦ Sw ≦ 200 (m ² / g)
(B) 1.0 ≦ As ≦ 7.5 (mg / m ² )
(E) 0.03 ≦ Dxs ≦ 1 (μm)
(F) Dys ≦ 30 (wt%)
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
AS: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxs: 50% cumulative particle weight average particle diameter (μm) calculated from the large particle side in the particle size distribution in the laser diffraction type (manufactured by Shimadzu Corporation: SALD-2000).
Dys: Cumulative weight (% by weight) of particle diameters exceeding 3 μm in the above particle size distribution
According to a third aspect of the present invention, the surface treated calcium carbonate is characterized by comprising calcium carbonate surface-treated with an organic surface treating agent and satisfying the following formulas (a) to (f).
(A) 20 ≦ Sw ≦ 200 (m ² / g)
(B) 1.0 ≦ As ≦ 7.5 (mg / m ² )
(C) 0.003 ≦ Dxp ≦ 0.03 (μm)
(D) 50 ≦ Dyp / Dxp ≦ 180
(E) 0.03 ≦ Dxs ≦ 1 (μm)
(F) Dys ≦ 30 (wt%)
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
As: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxp: In the mercury intrusion method, in the pore distribution in the pore range of 0.001 to 0.1 μm, the mercury intrusion increase amount (cumulative pore volume increase amount / 10 g average pore diameter) is the maximum value (Dys). Average pore diameter (μm)
Dyp: Maximum value of mercury intrusion increase (mg / l)
Dyp / Dxp: Average pore diameter Dxs: 50% average particle diameter (μm) of cumulative weight from the large particle side in the particle size distribution in the laser diffraction method (manufactured by Shimadzu Corporation: SALD-2000).
Dys: Cumulative weight (% by weight) of particle diameters exceeding 3 μm in the above particle size distribution
In the fourth aspect of the present invention, 0.5-15% by weight of a substance that forms a complex by coordination with metal ions is added to the calcium hydroxide slurry, and carbon dioxide is blown to synthesize calcium carbonate by a carbonation reaction. A method for producing a surface-treated calcium carbonate, characterized by adjusting the calcium carbonate concentration to 2.4 to 13.0% by weight and aging, and surface-treating the obtained calcium carbonate with an organic surface treatment agent Content.
According to a fifth aspect of the present invention, there is provided a resin composition characterized in that the surface-treated calcium carbonate is blended with a resin.
BEST MODE FOR CARRYING OUT THE INVENTION The details of the present invention will be specifically described below.
The formula (a) is a BET specific surface area of the surface-treated calcium carbonate of the present invention by a nitrogen adsorption method, and needs to be 20 to ²⁰⁰ m ² / g. When the specific surface area is less than 20 m ² / g, it is difficult to impart high viscosity, which is the object of the present invention. On the other hand, when it exceeds 200 m ² / g, it is preferable that the primary particles are very small, but the stability with time is poor and there is a problem in terms of dispersibility. Therefore, Preferably it is 30-150 m < ² > / g, More preferably, it is 40-120 m < ² > / g.
In addition, the apparatus for measuring a BET specific surface area used NOVA2000 type | mold by Yuasa Ionics.
The formula (b) is the amount of the organic surface treatment agent per unit specific surface area of the surface-treated calcium carbonate of the present invention, and the organic surface treatment amount As per unit specific surface area is 1.0 to 7.5 mg / m ² . It is necessary to be. Among conventional calcium carbonates, there are some commercially available fine primary particles that satisfy the formula (a). However, in the calcium carbonate, secondary particles formed by agglomeration of primary particles are further agglomerated. The surface treatment amount covering the calcium carbonate is less than 1.0 mg / m ² and is a sufficient treatment amount. However, the calcium carbonate of the present invention is more tertiary than the conventional one. Since there are few formed bodies and the dispersibility of the secondary particle formed body is extremely high, it is difficult to sufficiently cover the surface. Therefore, when drying and pulverization are performed while the treatment amount is insufficient, tertiary agglomerates are formed between the untreated surfaces, so that the effect as the surface-treated calcium carbonate cannot be sufficiently exhibited. On the other hand, when it exceeds 7.5 mg / m ² , the surface treatment agent is liberated to the resin component or the plastic component due to the excess of the surface treatment agent, causing a bleed phenomenon and a rough surface phenomenon. Therefore, Preferably it is 1.5-5.0 mg / m < ² >, More preferably, it is 2.0-4.0 mg / m < ² >.
The heat loss per unit specific surface area is TG-8110 manufactured by Rigaku Corporation. About 100 mg of surface-treated calcium carbonate is sampled on a sample pan (made of platinum) having a diameter of 10 mm and heated at a rate of 15 ° C./min. The heat loss up to ° C. was measured to determine the heat loss rate (mg / g) per gram of surface-treated calcium carbonate, and this value was divided by the BET specific surface area value.
Equations (c) and (d) serve as indices for knowing the dispersion state of the surface-treated calcium carbonate of the present invention.
(C) is an average pore diameter (Dxp) of a value (Dys) at which the amount of increase in mercury intrusion becomes maximum in the pore distribution in the range of 0.001 to 0.1 μm measured by the mercury intrusion method (porosimeter). It means the fineness of the gap between the surface treated calcium carbonate particles. Therefore, it represents the average diameter of the gaps between the primary particles, not the fineness of the particles shown by the (nitrogen) gas adsorption method of the formula (a), and it must be 0.003 to 0.03 μm. is there. When the average pore diameter is less than 0.003 μm, the primary particles or secondary particles are too fine, which causes a problem in stability over time. On the other hand, if it exceeds 0.03 μm, there are many secondary particle forming bodies in which the primary particles are too large or the primary particles are strongly agglomerated, and the high-viscosity physical property which is the object of the present invention is as follows. I can't get it. Therefore, it is preferably 0.005 to 0.025 μm, more preferably 0.006 to 0.020 μm.
The increase in the amount of mercury intrusion means the increase in the pore volume, and is expressed by the formula of (integrated pore volume increase / log average pore diameter) (unit: ml / g). Of course, the smaller the pore diameter, the smaller the pore volume, so the maximum mercury intrusion increase (Dys) depends on the pore diameter.
The formula (d) shows the number of average pore diameters of the formula (c), and is an index indicating the high viscosity that is the object of the present invention. As described above, the smaller the pore diameter, the smaller the pore volume. Therefore, it is necessary in the present invention by adding the maximum mercury intrusion increase amount (Dyp) and the average pore diameter (Dxp) of the formula (c). The amount (number) of pore diameters can be derived, and the higher the value of Dyp / Dxp, the higher the viscosity. Accordingly, it is necessary that the average pore diameter (Dyp / Dxp) of the present invention is 50 to 180. When Dyp / Dxp is less than 50, the high viscosity which is the object of the present invention cannot be obtained. On the other hand, if the average particle diameter exceeds 180, the average pore diameter is too small, which causes a problem in the temporal stability of the primary particles or secondary particles. Therefore, it is preferably 60 to 150, more preferably 70 to 130.
When the surface-treated calcium carbonate of the present invention is out of the ranges of the formulas (c) and (d), for example, the coating composition containing the calcium carbonate has low gloss, and the sealant composition has reduced strength at break. .
In addition, the mercury intrusion apparatus (porosimeter) used in the present invention and main measurement conditions are shown below.
<Measurement device>
Model 9520 manufactured by Shimadzu Corporation <Main measurement conditions>
Mercury purity = 99.99 (%)
Mercury surface tension = 480 (dyns / cm)
Mercury contact angle = 135 ° C
Cell constant = 10.79 (μl / pF)
Sample weight: Weighed to about 0.10 g each and measured The surface-treated calcium carbonate of the present invention may satisfy the following formulas (e) to (f), and further, the above formulas (a) to (d) In addition, it is preferable that the following expressions (e) to (f) are satisfied.
(E) 0.03 ≦ Dxs ≦ 1 (μm)
(F) Dys ≦ 30 (wt%)
However,
Dxs: 50% cumulative particle weight average particle diameter (μm) calculated from the large particle side in the particle size distribution in the laser diffraction type (manufactured by Shimadzu Corporation: SALD-2000).
Dys: Cumulative weight (% by weight) of particle diameters exceeding 3 μm in the above particle size distribution
The expressions (e) and (f) serve as indices for knowing the dispersion state in the resin composition, for example. Therefore, it is a preferred embodiment to add the above formula to the factor.
The particle size distribution was determined by weighing the following compounding materials (I) and (II) into a 140 ml mayonnaise bottle, stirring with a stainless spoon until they were visually dispersed, diluting with compounding material (III), and then using an ultrasonic disperser. Then, a pre-dispersed sample is used as a sample and measured by a laser diffraction particle size distribution meter (manufactured by Shimadzu Corporation: SALD-2000).
(I) Neutral detergent (5 times diluted with water) 2.0 g
(II) Calcium carbonate sample 0.4g
(III) Water 40g
In particular, it is preferable that the ultrasonic dispersion used as the pre-dispersion after adjusting with the above-described formulation as the pretreatment is performed under a certain condition, and the ultrasonic dispersion machine used in the examples of the present invention is US-300T (Nippon Seiki Seisakusho Co. And pre-dispersed under constant conditions of 100 μA-60 seconds. The neutral detergent is not particularly limited and is a general commercial product, and there is no problem. In the present invention, Mama Lemon (manufactured by Lion) was used.
In the particle size distribution measuring method described above, when the average particle diameter (Dxs) of the present invention is less than 0.03 μm, the temporal stability of the primary or secondary particles may be lowered. On the other hand, if it exceeds 1 μm, the number of tertiary particle forming bodies tends to increase as described above, and the dispersibility in the resin composition tends to deteriorate. Accordingly, the thickness is more preferably 0.05 to 0.8 μm, still more preferably 0.08 to 0.5 μm.
On the other hand, if the cumulative total weight (Dys) with an average particle diameter exceeding 3 μm exceeds 30% by weight, the dispersion state in the resin composition cannot be said to be sufficient, and it is difficult to obtain desired high viscosity properties. Therefore, it is more preferably 25% by weight or less, and most preferably 20% by weight or less.
When the surface-treated calcium carbonate of the present invention is out of the range of the above formulas (e) and (f), for example, the coating composition containing the calcium carbonate has reduced gloss, and the sealant composition has a breaking strength, etc. It is preferable that the surface-treated calcium carbonate of the present invention that easily causes problems further satisfy the following formulas (g) to (j). These define preferred ranges of the above-mentioned formulas (c), (d), (e), and (f), respectively.
(G) 0.005 ≦ Dxp ≦ 0.025 (μm)
(H) 60 ≦ Dyp / Dxp ≦ 150
(I) 0.05 ≦ Dxs ≦ 0.8 (μm)
(J) Dys ≦ 25 (% by weight)
It is preferable that the surface-treated calcium carbonate of the present invention further satisfies the following formula (k).
(K) 0.1 ≦ Sw · Dxp ≦ 1.5
The equation (k) is a value obtained by multiplying the BET specific surface area value (Sw) indicating the fineness of the surface-treated calcium carbonate primary particles by the average pore diameter (Dxp) indicating the fineness of the secondary particles. is there. The primary particles and the secondary particles are already individually limited by the formulas (a) to (j), but preferably not the individual but both have the desired viscosity as in the formula (k). It is easy to obtain physical properties. When Sw · Dxp in the formula (k) is less than 0.1, the temporal stability of the primary or secondary particles may be lowered. On the other hand, if it exceeds 1.5, the number of tertiary particle forming bodies tends to increase as described above. Therefore, it is more preferably 0.3 to 1.2, still more preferably 0.5 to 1.0.
The surface-treated calcium carbonate of the present invention preferably further satisfies the following formula (1).
(L) 0.03 ≦ Is ≦ 3 (μmol / m ² )
However,
Is: Alkali metal content per unit specific surface area calculated by the following formula {metal content per gram of calcium carbonate (μmol / g)} / Sw (m ² / g)
The formula (l) represents the alkali metal content in the surface-treated calcium carbonate, and is usually preferably in the range of 0.03 to 3 μmol / m ² . Among alkali metal compounds, especially sodium compounds are highly exothermic and easily react with moisture outside the system, so when sodium compounds in an amount exceeding 3 μmol / m ² are present in calcium carbonate, they are dispersed especially in sealing material applications. There may be problems in storage stability such as defects. Further, the alkali metal content of the To level or below 0.03μmol / ^{m 2} of 0.03μmol / ^{m 2} is 1) or very small the amount of surface treatment, 2) or excessive washing carried out after the surface treatment, 3) It is necessary to use an acid such as a fatty acid or a resin acid as a surface treatment agent. In the case of 1), the above-mentioned physical property defects are likely to occur, and in the case of 2), a large amount of water is required, resulting in an increase in cost. In the case of 3), since the surface treatment is performed at a temperature equal to or higher than the melting point, the cost tends to be high and the selectivity of the surface treatment agent is limited. Therefore, more preferably 0.15 to ² μmol / m ² , and still more preferably. Is 0.3 to 1.5 μmol / m ² .
As a more preferable aspect, in the calcium carbonate slurry before the surface treatment, it is preferable that the slurry behavior satisfies the following formula (m).
(M) 0.03 ≦ Dx ≦ 0.40
However,
Dx: Particle size (μm) at 50% cumulative weight calculated from the large particle size side in the particle size distribution measured with a centrifugal particle size distribution meter (SA-CP4, manufactured by Shimadzu Corporation)
The formula (m) represents the average particle diameter of the secondary particles before the surface treatment of the surface-treated calcium carbonate of the present invention, and incorporates a numerically clear particle size distribution index. The surface-treated calcium carbonate of the present invention that satisfies the formula (m) can surely exhibit the high viscosity imparting that is the object of the present invention. Therefore, when Dx is less than 0.03, problems are likely to occur in the temporal stability and dispersibility of the calcium carbonate primary particles. On the other hand, when it exceeds 0.40 μm, the proportion of the tertiary particle forming body is increased as described above, and thus it is difficult to obtain the high viscosity imparted object of the present invention in the surface-treated calcium carbonate. Therefore, it is more preferably 0.07 to 0.35 μm, and still more preferably 0.10 to 0.30 μm.
In addition, the primary particle shape of calcium carbonate can be used without particular limitation such as spherical shape, spindle shape, needle shape, lump shape, chain shape (necklace shape), etc. It is suitable not only for imparting viscosity but also for imparting resin strength.
As a more preferable aspect, the surface-treated calcium carbonate of the present invention preferably satisfies the following formula.
(N) VIS2 ≧ 400 (Pa · s)
(O) VIS20 ≧ 80 (Pa · s)
(P) VIS2 / VIS20 ≧ 5.0
However,
VIS2: viscosity of a mixed paste of diisononyl phthalate (DINP) and surface-treated calcium carbonate, BH viscometer at 2 rpm (Pa · s)
VIS20: 20 rpm viscosity (Pa · s) of the paste
(N)-(p) shows the viscous behavior in the resin component of the surface treatment calcium carbonate of this invention. A method for preparing a mixed paste of DINP and the calcium carbonate is as follows.
Calcium carbonate sample 50 parts by weight DINP 30 parts by weight DINP 30 parts by weight (additional)
30 parts by weight of DINP (additional)
(1) Take 30 g of DINP into a 1 L paper cup and then weigh out 50 g of calcium carbonate. A paper cup is set in a planetary stirring device KK-502N (manufactured by Kurabo Industries Co., Ltd.), kneaded for 60 seconds at 765 rpm for rotation and 765 rpm for revolution, and then hand-stirred with a stainless spoon, and then kneaded for 180 seconds.
(2) Add 30 g of DINP to the cup, knead for 60 seconds at 765 rpm for rotation and 765 rpm for revolution, and then knead manually with a stainless spoon, and then knead for 180 seconds.
(3) Further, 30 g of DINP is added to the cup, kneaded for 60 seconds at a rotation of 765 rpm and revolution of 765 rpm, followed by manual stirring with a stainless spoon, and then kneaded for 180 seconds to prepare a paste.
The paste prepared by the above method is allowed to cool at 20 ° C. for 12 hours, and then the viscosity at 2 rpm and 20 rpm is measured with a BH viscometer.
It is preferable that the paste viscosity created by the above method satisfies the formulas (n) to (p).
When VIS2 is less than 400 Pa · s, there are cases where the difference in sacrificing property and the like is not so large. When VIS20 is less than 80 Pa · s, it is difficult to obtain the desired viscosity of the present invention. Moreover, when VIS2 / VIS20 is less than 5.0, it becomes difficult to impart high thixotropy. Therefore, VIS2 ≧ 500, VIS20 ≧ 90, VIS2 / VIS20 ≧ 5.5, more preferably VIS2 ≧ 800, VIS20 ≧ 130, and VIS2 / VIS20 ≧ 6 are more preferable.
The method for producing calcium carbonate before the surface treatment of the surface-treated calcium carbonate of the present invention is not particularly limited. For example, as described in JP-A-10-72215, which is a conventional method, lime milk is mixed with calcium. The production method in which the complexing agent is added to terminate the carbonation reaction and then ripened is distinguished from the method of dispersion by, for example, the ripening concentration and the aging time. In the above conventional method, the fine particles dispersed are obtained by keeping the BET specific surface area after aging as high as possible. However, in order to achieve high viscosity and light weight as the problems of the present invention, further dispersion is required. Need to be prepared.
Preferred preparation conditions for the calcium carbonate used in the present invention are shown below.

A preferred method for producing calcium carbonate used in the present invention will be specifically described below.
(Reaction conditions)
The concentration of lime milk of (1) is preferably 3.5 to 10.2% by weight. When the lime milk concentration is less than 3.5%, not only the productivity is low and the cost is high, but even if the concentration is further reduced, it is difficult to expect improvement in dispersibility. On the other hand, if it exceeds 10.2% by weight, the primary particle size after the reaction tends to agglomerate, and even after aging, it becomes larger than the average secondary particle size and it is difficult to obtain desired viscosity properties. Therefore, it is more preferably 5.0 to 9.0% by weight, still more preferably 6.0 to 8.0% by weight.
The addition amount of the complex-forming substance (2) is preferably 0.5 to 15% by weight. When the addition amount is less than 0.5% by weight, it is difficult to obtain the intended fine particles of the present invention. On the other hand, when the addition amount exceeds 15% by weight, the primary particles after the reaction are too fine. The diameter may not satisfy the range of formula (f), which is a preferable dispersion state, and as a result, it is difficult to obtain a desired high viscosity. At the time of addition, either before the carbonation reaction or during the carbonation reaction, it may be added both before and during the reaction.
Complex forming substances include hydroxycarboxylic acids such as citric acid, oxalic acid and malic acid and alkali metal salts thereof, alkaline earth metal salts and ammonium salts; polyhydroxycarboxylic acids such as gluconic acid and tartaric acid and alkali metal salts thereof; Alkaline earth metal salts and ammonium salts; aminopolycarboxylic acids such as iminodiacetic acid, ethylenediaminetetraacetic acid, nitrilotriacetic acid and their alkali metal salts, alkaline earth metal salts and ammonium salts; polyacetic acids such as hexametaphosphoric acid and tripolyphosphoric acid and their alkalis Metal salts, alkaline earth metal salts and ammonium salts; ketones such as acetylacetone, methyl acetoacetate and allyl acetoacetate; sulfuric acid and alkali metal salts thereof, alkaline earth metal salts and ammonium salts, etc. Use more than one type in combination Possible it is. Of these, hydroxycarboxylic acids have high binding properties with calcium, and citric acid can be preferably used.
The carbon dioxide gas flow rate of (3) is usually 300 to 3000 L / hr per 1 kg of calcium hydroxide. If it is less than 300 L / hr, the primary particles after the reaction tend to be large, and if it exceeds 3000 L / hr, the cost is industrially increased.
Regarding the gas concentration of (4), 10 to 50% is preferable. When the gas concentration is less than 10%, the primary particles after the reaction tend to be large, and when it exceeds 50%, the cost is industrially increased.
(Maturation conditions)
Regarding the calcium carbonate concentration of (5), 2.4 to 13.0% by weight is preferable. When the amount is less than 2.4% by weight, the productivity is industrially low. On the other hand, when the amount exceeds 13.0% by weight, the system is uniformly stirred when the dispersibility is improved by aging and the structural viscosity of the system is increased. In some cases, the average secondary particle size may not satisfy the range of the formula (f). As a result, it becomes difficult to obtain a desired high viscosity. Therefore, it is more preferably 4.0 to 11.0% by weight, still more preferably 5.0 to 9.0% by weight.
As described above, the ripening concentration tends to be an important index for improving the dispersibility. Therefore, it is more effective to reduce the concentration to a preferable range for finer particles.
Regarding the ripening time of (6), it is preferable to ripen to a level satisfying the formula (f), which is a preferred range as an index of dispersibility, because the expression of imparting high viscosity, which is the object of the present invention, can be easily obtained. Accordingly, the aging time depends on the production conditions described above, and thus the aging time is not particularly limited, but usually 24 to 240 hours is preferable. If the aging time is less than 24 hours, it is difficult to obtain desired dispersed particles, and if it exceeds 240 hours, the cost is increased industrially. Therefore, it is more preferably 30 to 200 hours, still more preferably 40 to 180 hours.
Manufacturing conditions other than those described above may be performed in the conventional manner. For example, the synthesis temperature condition is usually in the range of 5 to 30 ° C, and the aging temperature condition is usually in the range of 30 to 70 ° C. In addition, the stirring conditions at the time of aging are sufficient as long as the entire liquid system can be stirred uniformly. However, if the conventional stirring capacity is used, the concentration of the system will inevitably need to be reduced. It tends to be high. From the viewpoint of improving dispersibility as well as productivity, it is preferable that the stirring ability is higher than the conventional one. In addition, a paddle, a turbine, a propeller, a high-speed impeller, etc. are generally used also as a stirring mechanism.
(surface treatment)
Since the surface treatment amount of (7) depends on the specific surface area of the calcium carbonate dough, it is not particularly limited as long as it is within the range of As in the formula (b), but usually 3.5 to 50% by weight It is. When the surface treatment amount is less than 3.5% by weight, the surface of the fine and highly dispersible calcium carbonate of the present invention may not be sufficiently covered. As a result, secondary agglomeration is formed between untreated surfaces during drying and pulverization, so that the effect as the surface-treated calcium carbonate cannot be sufficiently exhibited. On the other hand, if it exceeds 50% by weight, the resin component or the plastic component is liberated due to excessive surface treatment agent, which tends to cause a bleed phenomenon or a rough surface phenomenon. Therefore, it is more preferably 5 to 40% by weight, still more preferably 7 to 35% by weight. The surface treatment method is not particularly limited, and may be either wet or dry.
The organic surface treating agent used in the present invention is represented by caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, saturated fatty acid represented by araginic acid, oleic acid, elaidic acid, linoleic acid, and ricinoleic acid. Unsaturated fatty acids, alicyclic carboxylic acids typified by naphthenic acid, abietic acid, pimaric acid, parastrinic acid, resin acids typified by neoabietic acid and their disproportionated rosin, hydrogenated rosin, dimer Rosin, modified rosin represented by trimer rosin, sulfonic acid represented by alkylbenzene sulfonic acid, and alkali metal salts, alkaline earth metal salts, ammonium salts, amine salts thereof, and anionic properties exemplified below , Cationic and nonionic surfactants can be used alone or in combination of two or more. A. In particular, an alkali metal salt of a fatty acid and an alkali metal salt of a resin acid are preferable from the viewpoint of adsorption reactivity with calcium carbonate.
Examples of the anionic surfactant include alkyl ether sulfuric acid exemplified by polyoxyethylene alkyl ether sulfuric acid, alkyl ether phosphoric acid exemplified by polyoxyethylene alkyl ether phosphoric acid, polyoxyethylene alkyl phenyl ether sulfuric acid and the like. Alkyl aryl ether sulfuric acid, alkyloxy ether exemplified by polyoxyethylene alkyl phenyl ether phosphoric acid, etc., alkyl sulfuric acid ester exemplified by polyoxyalkyl sulfuric acid ester, etc., alkyl phosphoric acid ester exemplified by polyoxyalkyl phosphoric acid ester, etc. Alkylaryl sulfates exemplified by polyoxyalkylphenyl sulfates, alkylaryl phosphates exemplified by polyoxyalkylphenyl phosphates, fatty acid alkyls Illustrated by alkylamide sulfates exemplified by roll amide sulfates, alkyl sulfonates exemplified by polyoxyethylene alkyl sulfonates, alkyl benzene sulfonates, alkyl naphthalene sulfonates, sulfosuccinates, dialkyl sulfosuccinates, etc. Sulfosuccinic acid esters, α-olefin sulfonic acids, N-acyl sulfonic acids and / or anionic surfactants such as alkali metals, alkaline earth metal salts, amine salts, ammonium salts, α, β unsaturated monocarboxylic acids Acid, α, β unsaturated dicarboxylic acid, methacrylic acid alkyl ester, (meth) acrylic ether having alkoxy group, (meth) acrylate having cyclohexyl group, α, β monoethylenically unsaturated hydroxy ester, polyalkylene group Copolymers comprising recalled mono (meth) acrylate, vinyl ester, vinyl aromatic, unsaturated nitrile, unsaturated dicarboxylic acid ester, vinyl ether, conjugated diene, chain olefin, cyclic olefin, sulfo group-containing monomer, etc. And an anionic polymer dispersant exemplified by the above, and a partially neutralized or completely neutralized salt of these with an alkali metal, alkaline earth metal, ammonium or the like.
Examples of cationic surfactants include aliphatic amine salts such as stearylamine acetate and stearylamine hydrochloride, aliphatic quaternary ammonium salts such as lauryltrimethylammonium chloride and stearyltrimethylammonium chloride, and alkylbenzyldimethylammonium chloride. Cationic surfactants such as aromatic quaternary ammonium salts, heterocyclic quaternary ammonium compounds, amino groups (primary amine groups), imino groups (secondary amine groups), tertiary amine groups, quaternary ammonium groups, Cationic polymer dispersants having polar groups such as hydrazino groups, monomers copolymerizable with monomers having these polar groups, such as α, β unsaturated monocarboxylic acids, α, β unsaturated dicarboxylic acids Acids, alkyl methacrylates, (meth) alkoxy groups Ryl ether, (meth) acrylate having cyclohexyl group, α, β monoethylenically unsaturated hydroxy ester, polyalkylene glycol mono (meth) acrylate, vinyl ester, vinyl aromatic, unsaturated nitrile, unsaturated dicarboxylic acid ester, vinyl ether , Copolymers with monomers such as conjugated dienes, chained olefins, cyclic olefins, sulfo group-containing monomers, and salts partially or completely neutralized by alkali metals, alkaline earth metals, ammonium, etc. Is given as an example.
Furthermore, examples of nonionic surfactants include betaine, aminocarboxylic acid, and imidazoline derivatives exemplified by polyoxyethylene and derivatives thereof, carboxybetaine, sulfobetaine and the like.
After the surface treatment, it is preferable to filter and wash contaminated ions such as alkali metal ions contained in the slurry so as to satisfy the above-described formula (f). The electrical conductivity of the filtrate is not particularly limited, but is usually 10 mS / cm or less, more preferably 1 mS / cm or less, and still more preferably 300 μS / cm or less.
There is no restriction | limiting in particular about the washing method, Thickener, an oliver, a rotary filter, a Larox press etc. can be used and washing and concentration can be performed.
As described above, the surface-treated calcium carbonate of the present invention is particularly suitable for resins. For example, it is blended in various resins such as molding resins, paint resins, ink resins, sealant resins, and adhesive resins. The resin composition has excellent characteristics and physical properties.
The molding resin is not particularly limited, but for example, ABS resin, fluororesin, polyethylene terephthalate, polycarbonate, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene or a copolymer of propylene and other monomers, etc. Represented by polyolefin resins, polystyrene resins, acrylic resins, methacrylic resins, vinyl chloride resins, vinylidene chloride resins, polyamide resins, polyether resins, vinyl acetate resins, polyvinyl alcohol resins, etc. Thermosetting resins such as thermoplastic resins, phenol resins, urea resins, melamine resins, epoxy resins, polyurethane resins, polyimide resins and the like can be exemplified, and these resin components can be used alone or in combination of two or more. used.
The blending ratio of the surface-treated calcium carbonate of the present invention and these resins is not particularly limited, and may be appropriately determined according to desired physical properties. Usually, the surface-treated calcium carbonate is 1 to 100 parts per 100 parts by weight of the resin. Part by weight is preferred. Of course, various additives such as a stabilizer may be added as necessary.
The resin for paint is not particularly limited, but is a solvent-based paint represented by alkyd resin, acrylic resin, vinyl acetate resin, urethane resin, silicone resin, fluororesin, styrene resin, melamine resin, epoxy resin, etc. For resin and water-based paints, alkyd resin, acrylic resin, latex resin, vinyl acetate resin, urethane resin, silicone resin, fluororesin, styrene resin, melamine resin, epoxy resin, etc. Resin, amine resin, styrene-allyl alcohol resin, amino alkyd resin, polybutadiene resin, and other general water-soluble resin for paints, dispersion resin for paints blended with emulsion resin and water-soluble resin, and cross-linked water-soluble resin Dispersion tree as emulsifier , It can be exemplified an acrylic hydrosol. These resin components may be used alone or in combination of two or more kinds.
The blending ratio of the surface-treated calcium carbonate of the present invention and these resins is not particularly limited, and may be appropriately determined according to desired physical properties. Usually, the surface-treated calcium carbonate is 1 to 100 parts per 100 parts by weight of the resin. Part by weight is preferred. Of course, various additives such as a plasticizer and a dispersant may be added as necessary.
Examples of the plastisol resin include vinyl chloride sol, acrylic sol, water-soluble acrylic sol, and urethane sol. These resin components are used alone or in combination of two or more.
The blending ratio of the surface-treated calcium carbonate of the present invention and these resins is not particularly limited, and may be appropriately determined according to desired physical properties. Usually, the surface-treated calcium carbonate is 1 to 100 parts per 100 parts by weight of the resin. Part by weight is preferred. Of course, various additives such as a stabilizer may be added as necessary.
The resin for ink is not particularly limited, but rosin modified phenolic resin, urea resin, melamine resin, ketone resin, polyvinyl chloride resin, polyvinyl chloride-vinyl acetate copolymer, butyral resin, styrene-maleic acid Examples include resin, chlorinated polypropylene, acrylic resin, coumarone / indene resin, petroleum resin, polyester resin, alkyd resin, polyamide resin, epoxy resin, polyurethane resin, nitrocellulose, ethylcellulose, ethylhydroxycellulose, cyclized rubber, chlorinated rubber, etc. These resin components are used alone or in combination of two or more.
The blending ratio of the surface-treated calcium carbonate of the present invention and these resins is not particularly limited, and may be appropriately determined according to desired physical properties. Usually, the surface-treated calcium carbonate is 1 to 100 parts per 100 parts by weight of the resin. Part by weight is preferred. Of course, various additives such as a stabilizer and a dryer may be added as necessary.
The sealant resin is not particularly limited, but examples thereof include polyurethane resin, polysulfide resin, silicone resin, modified silicone resin, polyisobutylene resin, epoxy resin, polyester resin, and the like. Or two or more types are used in combination.
The blending ratio of the surface-treated calcium carbonate of the present invention and these resins is not particularly limited, and may be appropriately determined according to desired physical properties. Usually, the surface-treated calcium carbonate is 1 to 100 parts per 100 parts by weight of the resin. Part by weight is preferred. Of course, various additives such as a colorant and a stabilizer may be added as necessary.
The resin for adhesive is not particularly limited, but examples include urea resins, phenol resins, epoxy resins, silicone resins, acrylic resins, polyurethane resins, polyester resins, and the like, and these resin components are used alone or Used in combination of two or more.
The blending ratio of the surface-treated calcium carbonate of the present invention and these resins is not particularly limited, and may be appropriately determined according to desired physical properties. Usually, the surface-treated calcium carbonate is 1 to 100 parts per 100 parts by weight of the resin. Part by weight is preferred. Of course, various additives such as a stabilizer and a plasticizer may be added as necessary.
In addition to the surface-treated calcium carbonate of the present invention, the resin composition of the present invention includes colloidal calcium carbonate, heavy calcium carbonate, colloidal silica, talc, kaolin, zeolite, resin in order to adjust viscosity and other physical properties. Fillers such as balloons and glass balloons, plasticizers such as dioctyl phthalate and dibutyl phthalate, petroleum solvents such as toluene and xylene, ketones such as acetone and methyl ethyl ketone, solvents exemplified by ether esters such as cellosolve acetate, or Various additives such as silicone oil and fatty acid ester-modified silicone oil, and various additives, colorants and the like can be added alone or in combination of two or more.
In the case of a curable resin composition represented by a sealant and an adhesive, for example, the resin composition of the present invention has excellent viscosity / thixotropic properties and joint followability. For example, in the case of a resin composition for paints and inks, it has excellent sagging resistance, high gloss, high transparency, and high coating strength. Furthermore, for example, in the case of a molding resin composition, a decrease in the strength of the weld line surface is prevented, and the resin composition has excellent strength.
Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these unless it exceeds the gist.
In the following description, “%” means “% by weight” and “part” means “part by weight” unless otherwise specified.
Example 1
1.7% citric acid as a complex-forming substance is added to calcium hydroxide at a temperature of 10 ° C. and a concentration of 8%, and 1700 L / hr of 20% CO ₂ gas per 1 kg of calcium hydroxide is introduced into the slurry. A calcium carbonate slurry was prepared. Next, the calcium carbonate slurry was adjusted to a concentration of 10%, and stirred and aged at a temperature of 45 to 50 ° C. for 50 hours. The average particle size (Dx) after aging was 0.20 μm. The surface treatment agent is sufficiently adsorbed on the surface of calcium carbonate by adding 10% sodium stearate dissolved in hot water to the calcium carbonate slurry by 15% with respect to the solid content of calcium carbonate, followed by dehydration. Then, it was dried and powdered to synthesize calcium carbonate obtained by surface-treating an organic surface treatment agent having a BET specific surface area (Sw) = 48 m ² / g. In addition, it was 200 to 500 degreeC heat loss rate (Tg) = 118 mg / g of this surface treatment calcium carbonate. The average pore diameter (Dxp) = 0.016 μm and the average pore diameter (Dyp / Dxp) = 79. Table 1 shows the physical property values of the obtained surface-treated calcium carbonate.
Example 2
Except for changing the calcium carbonate slurry concentration to 7%, calcium carbonate obtained by surface-treating an organic surface treatment agent by the same production method as in Example 1 was synthesized. Table 1 shows the physical property values of the obtained surface-treated calcium carbonate.
Example 3
Calcium carbonate obtained by surface-treating an organic surface treatment agent was synthesized by the same production method as in Example 2 except that the aging time was changed to 120 hours. Table 1 shows the physical property values of the obtained surface-treated calcium carbonate.
Example 4
After the surface treatment, the organic surface treatment agent was applied to the surface by the same production method as in Example 1 except that the calcium carbonate cake was washed with water and dehydrated until the filtrate had a conductivity of 300 μS / cm using a filter press (manufactured by Lalox). The treated calcium carbonate was synthesized. Table 1 shows the physical property values of the obtained surface-treated calcium carbonate.
Example 5
Calcium carbonate formed by surface-treating an organic surface treatment agent was synthesized by the same production method as in Example 1 except that the surface treatment amount was changed to 25%. Table 1 shows the physical property values of the obtained surface-treated calcium carbonate.
Example 6
10% citric acid as a complex-forming substance is added to calcium hydroxide at a temperature of 10 ° C. and a concentration of 5%, and 1700 L / hr of 20% CO ₂ gas per 1 kg of calcium hydroxide is introduced into the slurry, A calcium carbonate slurry was prepared. Next, the calcium carbonate slurry was adjusted to a concentration of 3%, and stirred and aged at a temperature of 45 to 50 ° C. for 150 hours. The average particle size (Dx) after aging was 0.38 μm. After 35% of 10% sodium stearate dissolved in hot water is dissolved in the calcium carbonate slurry with respect to the solid content of calcium carbonate, the surface treatment agent is sufficiently adsorbed on the calcium carbonate surface by stirring, and then dehydrated. Then, it was dried and pulverized to synthesize calcium carbonate obtained by surface-treating an organic surface treatment agent having a BET specific surface area (Sw) = 125 m ² / g. In addition, it was 200 to 500 degreeC heat loss rate (Tg) = 296 mg / g of this surface treatment calcium carbonate. Further, the average pore diameter (Dxp) = 0.005 μm and the average pore diameter (Dyp / Dxp) = 148. Table 1 shows the physical property values of the obtained surface-treated calcium carbonate.
Example 7
As a complex-forming substance, calcium carbonate obtained by surface-treating an organic surface treatment agent was synthesized by the same production method as in Example 1 except that 3% of trisodium citrate was added to calcium hydroxide. Table 1 shows the physical property values of the obtained surface-treated calcium carbonate.
Example 8
Calcium carbonate obtained by surface-treating the organic surface treatment agent was synthesized by the same production method as in Example 1 except that the organic surface treatment agent was changed to lauric acid. Table 1 shows the physical property values of the obtained surface-treated calcium carbonate.
Example 9
Calcium carbonate obtained by surface-treating the organic surface treatment agent was synthesized by the same production method as in Example 1 except that the organic surface treatment agent was changed to sodium laurate. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Example 10
Calcium carbonate obtained by surface-treating the organic surface treatment agent was synthesized by the same production method as in Example 1 except that the organic surface treatment agent was changed to sodium palmitate. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Example 11
Calcium carbonate obtained by surface-treating the organic surface treatment agent was synthesized by the same production method as in Example 1 except that the organic surface treatment agent was changed to sodium stearate: potassium resinate = 3: 2. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Example 12
Calcium carbonate obtained by surface-treating the organic surface treatment agent was synthesized by the same production method as in Example 1 except that the organic surface treatment agent was changed to potassium resinate. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Example 13
Calcium carbonate formed by surface-treating the organic surface treatment agent was synthesized by the same production method as in Example 1 except that the organic surface treatment agent was changed to sodium stearate: sodium alkylbenzenesulfonate = 3: 1. . Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Comparative Example 1
Calcium carbonate obtained by surface-treating the organic surface treatment agent was synthesized by the same production method as in Example 1 except that the addition amount of the organic surface treatment agent was changed to 5%. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Comparative Example 2
18% citric acid as a complex-forming substance is added to calcium hydroxide at a temperature of 10 ° C. and a concentration of 4%, and 17,000 L / hr of 20% CO ₂ gas per 1 kg of calcium hydroxide is introduced into the slurry, A calcium carbonate slurry was prepared. Next, the calcium carbonate slurry was adjusted to a concentration of 2%, and stirred and aged at a temperature of 45 to 50 ° C. for 200 hours. The average particle size (Dx) after aging was 2.3 μm. After adding 45% of 10% sodium stearate dissolved in hot water to the calcium carbonate slurry with respect to the solid content of calcium carbonate, the surface treatment agent was sufficiently adsorbed on the calcium carbonate surface by stirring, and then dehydrated. Then, it was dried and powdered to synthesize calcium carbonate obtained by surface-treating an organic surface treatment agent having a BET specific surface area (Sw) = 175 m ² / g. In addition, it was 200 to 500 degreeC heat loss rate (Tg) = 402 mg / g of this surface treatment calcium carbonate. Further, the average pore diameter (Dxp) = 0.003 μm and the average pore diameter (Dyp / Dxp) = 47. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Comparative Example 3
As in Example 1 of JP-A-10-72215, 3% trisodium citrate as a complex-forming substance is added to calcium hydroxide at a temperature of 10 ° C. and a concentration of 11.8%, and the slurry is added to the slurry. A calcium carbonate slurry was prepared by introducing 1700 L / hr of 20% CO ₂ gas per 1 kg of calcium hydroxide. Next, the calcium carbonate slurry was stirred and aged for 50 minutes at a temperature of 45 to 50 ° C. while maintaining the calcium carbonate concentration of 14.9% without adjusting the concentration. The average particle size (Dx) after aging was 0.50 μm. To the calcium carbonate slurry, 15% of 10% sodium stearate dissolved in hot water is added to the calcium carbonate solid content, and the surface treatment agent is sufficiently adsorbed on the calcium carbonate surface by vigorous stirring. Calcium carbonate was synthesized by dehydration, drying and pulverization, and surface treatment with an organic surface treatment agent having a BET specific surface area (Sw) of 42 m ² / g. In addition, it was 200 to 500 degreeC heat loss rate (Tg) = 101 mg / g of this surface treatment calcium carbonate. Moreover, it was average pore diameter (Dxp) = 0.018m, average pore diameter amount (Dyp / Dxp) = 27. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Comparative Example 4
A lime milk having a temperature of 10 ° C. and a concentration of 11.8% is added with 0.2% citric acid as a complex-forming substance with respect to calcium hydroxide, and 1700 L / hr of 20% CO ₂ gas per 1 kg of calcium hydroxide is added to the slurry. Was introduced to prepare calcium carbonate. Next, the calcium carbonate slurry was aged and stirred for 50 minutes at a temperature of 45 to 50 ° C. with the calcium carbonate concentration of 14.9% without adjusting the concentration. The average particle size (Dx) after aging was 0.49 μm. To the calcium carbonate slurry, 5% of 10% sodium stearate dissolved in hot water with respect to the solid content of calcium carbonate is added, and the surface treatment agent is sufficiently adsorbed on the calcium carbonate surface by vigorous stirring. Calcium carbonate was synthesized by dehydration, drying and pulverization, and surface treatment with an organic surface treatment agent having a BET specific surface area (Sw) = 17 m ² / g. In addition, it was 200 mg-500 degreeC heat loss rate (Tg) = 42 mg / g of this surface treatment calcium carbonate.
The average pore diameter (Dxp) was 0.042 m, and the average pore diameter (Dyp / Dxp) was 38. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.
Comparative Example 5
Calcium carbonate obtained by surface-treating the organic surface treatment agent was synthesized by the same production method as in Comparative Example 3 except that the organic surface treatment agent was changed to potassium resinate. Table 2 shows each physical property value of the obtained surface-treated calcium carbonate.

Examples 14-20, Comparative Examples 6-9
Using the surface-treated calcium carbonate synthesized in Examples 1 to 7 and Comparative Examples 1 to 4, a molding resin composition was prepared based on the following formulation. Table 3 shows the evaluation results of the obtained molded resin composition.
(Combination)
Surface treated calcium carbonate 15 parts Polypropylene resin 85 parts The above two types are dry blended with a Henschel mixer (manufactured by Kawata), then pelletized with an extruder (NEXT T-60, manufactured by Kobe Steel), and then injection molded. Dumbbell pieces were produced by a machine and tested for tensile strength, flexural modulus, and impact strength. However, the test piece for measuring the strength of the weld line surface was injected from two gates to form a weld line interface in the middle. Other specimens for measuring physical properties were injected from one gate.
Various characteristics of the obtained test piece were measured and evaluated by the following methods.
(Tensile strength, bending strength, impact strength)
Tensile strength was determined in accordance with a plastic tensile test method of JIS K7113, bending strength was determined in accordance with a hard plastic bending test method of JIS K7203, and impact strength was determined in accordance with a JIS K7111 hard plastic Charpy impact test method.
(Scratch test)
A plastic plate molded to 30 mm × 80 mm thickness 1 mm was subjected to a scratch test using a scratch tester (manufactured by Toyo Seiki Seisakusho Co., Ltd.), and the state was evaluated according to the following criteria.
A: Very good (no scratches at all)
○: Good (nearly scratched)
Δ: Normal (slightly scratched)
X: Defect (slightly scratched)

As is apparent from the results in Table 3, the molding resin composition comprising the surface-treated calcium carbonate of the present invention is not only excellent in tensile strength, bending strength, and impact strength, but also in the strength of the weld line surface. It is excellent also in prevention of a fall, and it turns out that it is excellent also in the adhesive force with to-be-adhered thing from this. In addition, it was confirmed that the amount of calcium carbonate added can be reduced by about 5% compared to the prior art, and it is also effective in reducing the weight.
Examples 21-27, Comparative Examples 10-13
Using the surface-treated calcium carbonate synthesized in Examples 1 to 7 and Comparative Examples 1 to 4, paint resin compositions were prepared based on the following formulation.
(Combination)

The above blend was dispersed with an SG mill until the particle gauge became 20 microns or less, and then glass beads were removed to prepare a coating resin composition. Various properties were measured and evaluated by the following methods. The results are shown in Table 4.
(Gloss, gloss after water resistance test, gloss retention)
Each paint resin composition was applied to one side of a glass plate using a 100 micron applicator, dried at room temperature for 24 hours, and then measured for 60 ° gloss with a Murakami gloss meter. Then, the glass plate was immersed in water and the gloss retention after 3 days was measured.
(Sagging)
Each coating resin composition is diluted with mineral spirit so that the KU value is 78, and applied to all black measurement paper using an applicator of 250, 200, 150, and 100 microns. Was stood so as to be vertical and allowed to stand at room temperature for 24 hours, and the sagging state was evaluated according to the following criteria.
○: Good (no sagging at all)
Δ: Normal (slightly leaning)
X: Defect (sagging)
(Scratch test of coating film)
Each paint resin composition is applied to one side of a glass plate using a 1000 micron applicator, dried at room temperature for 1 week, and then subjected to a scratch test using a scratch tester (manufactured by Toyo Seiki Seisakusho). Evaluation was made according to the following criteria.
A: Very good (no scratches at all)
○: Good (nearly scratched)
Δ: Normal (slightly scratched)
X: Defect (slightly scratched)

As is apparent from the results in Table 4, the coating resin composition formed by blending the surface-treated calcium carbonate of the present invention is excellent in sagging resistance, and thus has high thixotropy and water resistance. The gloss retention after the property test is excellent, and this shows that it has high durability and strong coating strength.
Examples 28-34, Comparative Examples 14-17
Using the surface-treated calcium carbonate synthesized in Examples 1 to 7 and Comparative Examples 1 to 4, plastisol resin compositions adjusted based on the following formulation were prepared.
(Combination)
Surface treatment Calcium carbonate 300 parts Acrylic resin Zeon acrylic resin F345 (manufactured by Shin-Daiichi Vinyl Industrial Co., Ltd.) 250 parts Block urethane resin curing agent (Mitsui Takeda Chemical Co., Ltd.) 120 parts DINP 500 parts Turpen 80 parts Urethane curing agent (Mitsui Takeda Chemical) 6 parts, respectively, were kneaded with a 5 L universal stirrer (manufactured by Dalton Co.) at room temperature until no tabs were formed to prepare an acrylic sol resin composition, and various properties were measured and evaluated by the following methods. The results are shown in Table 5.
(Viscosity / thixotropic)
The viscosity of the acrylic sol adjusted based on the above formulation was measured at 2 rpm and 20 rpm using a BH viscometer, and 2 rpm viscosity / 20 rpm viscosity was displayed as thixotropy.
(Chip resistance)
The coating film after baking and curing on the electrodeposition coating plate under the above-mentioned drying conditions is fixed at an angle of 60 ° from the horizontal with the coating surface facing up, and the lower end of a 2 m long pipe standing vertically to the coating surface The M-4 nut was dropped according to the JIS nut drop test method, and the chipping resistance was expressed by the integrated weight of the nut until the coated surface was broken and the base was exposed.

As is clear from the results in Table 5, it was confirmed that the plastisol resin composition containing the calcium carbonate obtained by surface treatment of the present invention has clearly improved viscosity and strength (chipping resistance). It was.
Examples 35-46, Comparative Examples 18-21
Using the surface-treated calcium carbonate synthesized in Examples 1 to 11 and 13 and Comparative Examples 1 to 4, adjustment was made based on the following formulation, and various characteristics of the obtained cured resin compositions were evaluated. The results are shown in Tables 6 and 7.
(Combination)
(Base material)

Each compound was sufficiently kneaded with a 5 liter universal mixing stirrer (Dalton) until no crumbs were formed to prepare a base material and a curing agent, and various properties were measured and evaluated by the following methods. The results are shown in Table 6.
(Viscosity / thixotropic)
The substrate viscosity of the cured resin composition adjusted based on the above formulation was measured at 1 rpm and 10 rpm using a BS viscometer, and 1 rpm viscosity / 10 rpm viscosity was displayed as thixotropy.
(Storage stability test)
The base viscosity of the cured resin composition after standing at 20 ° C. for 2 weeks was measured.
(H type tensile strength and elongation test)
Substrate: Curing agent = 10: 1 was sufficiently defoamed and mixed, and an H-type was prepared and evaluated based on JIS A5757 6.11 tensile stress and elongation test.
(Adhesion test)
In the H-type tensile strength test, the adhesion was evaluated according to the following criteria.
○: Good (material is destroyed)
Δ: Normal (Slight interface peeling but material destruction)
X: Defect (exfoliation at the interface)
(After follow-up test, H-type tensile test and adhesion test)
In the H-type tensile strength test, the cured product was fixed for one week in a state of being stretched by 50%, and then the H-type tensile strength (residual stress) was measured in the same manner and the adhesiveness was evaluated. The followability to the joint was evaluated.

As is apparent from the results of Tables 6 and 7, the cured resin composition represented by the sealant and adhesive, which is formed by blending the calcium carbonate obtained by surface treatment of the present invention, has high breaking strength and is attached. It was excellent in the adhesive strength with the body, and it was confirmed that the effect was maintained even after the followability test.
Moreover, it was confirmed that the storage stability was excellent by reducing the alkali metal content in calcium carbonate by washing as in Examples 4 and 8.
Example 47, Comparative Example 22
Using the surface-treated calcium carbonate synthesized in Example 12 and Comparative Example 5, an ink resin composition was prepared based on the following formulation. Table 8 shows the evaluation results of the obtained ink resin composition.
(Combination)
Surface treatment Calcium carbonate 25 parts Rosin modified phenolic resin 35 parts Linseed oil 20 parts Refined light oil 17 parts Dryer 3 parts The above compound is dispersed using 3 rolls (Inoue Seisakusho) until the particle gauge is 5 microns or less. To prepare an ink resin composition.
(Viscosity / thixotropic)
The ink resin composition prepared based on the above formulation was measured for viscosity at 1 rpm and 10 rpm using a BS viscometer, and 1 rpm viscosity / 10 rpm viscosity was displayed as thixotropy.
(transparency)
The ink resin composition prepared on the basis of the above composition was applied to one side of a glass plate using a 25 micron applicator, dried at room temperature for 24 hours, and then lighted at 550 μm using a photoelectric spectrophotometer (manufactured by Shimadzu Corporation). The transmittance was measured.
(Glossy)
The ink resin composition was applied in the same manner as described above, dried at room temperature for 24 hours, and then measured for 60 ° gloss with a Murakami type gloss meter.
(Abrasion resistance test)
Each resin composition was applied to one side using a 25-micron applicator on all black measurement paper, dried at room temperature for 24 hours, and then based on the JISK5701 rub resistance test, S-type abrasion tester (Sutherland Lab Tester) The following criteria were used for evaluation.
○: Good (not worn)
Δ: Normal (slightly worn)
X: Defect (wears considerably)
(Adhesiveness)
After coating and drying in the same manner as described above, Cellotape (registered trademark) [CT405A-18 manufactured by Nichiban Co., Ltd.] was applied to the surface of the coating film, and then rapidly peeled off. The peeled state of the ink was evaluated according to the following criteria.
A: Very good (not peeled at all)
○: Good (almost no peeling)
Δ: Normal (slightly peels off)
X: Defect (exfoliates considerably)
(Scratch resistance)
After coating and drying in the same manner as described above, a scratch test was performed using a scratch tester (manufactured by Toyo Seiki Seisakusho Co., Ltd.), and the state was evaluated according to the following criteria.
A: Very good (no scratches at all)
○: Good (nearly scratched)
Δ: Normal (slightly scratched)
X: Defect (slightly scratched)

As is apparent from the results in Table 8, it can be seen that the ink resin composition obtained by blending the surface-treated calcium carbonate of the present invention is not only excellent in the viscosity / thixotropic property imparting effect, but also has high gloss and transparency. Further, it can be seen that the film is excellent in wear resistance and scratch resistance, has high coating strength, and has excellent adhesion to an adherend. As a result, the amount of calcium carbonate added can be reduced as compared with the prior art, which is effective in stabilizing the ink characteristics.
Industrial Applicability As described above, calcium carbonate having a specific particle size characteristic obtained by surface-treating the organic surface treatment agent of the present invention is particularly useful for a resin, and when incorporated in a resin, the calcium carbonate has a specific particle size characteristic. It is possible to improve the adhesive force between the resin composition and the adherend and to form a tough coating film.
When the surface-treated calcium carbonate of the present invention is used, for example, as a molding resin, a decrease in the strength of the weld line surface is prevented, and a resin composition having excellent impact strength is used, for example, in paints and inks. In this case, when a resin composition having high gloss, excellent sagging resistance, and high coating strength is used, for example, as a resin composition for plastisol, a resin having excellent viscosity, thixotropy and chipping resistance. When the composition is used for, for example, a curable resin typified by a sealant or an adhesive, a resin composition having excellent viscosity / thixotropy and joint followability can be provided.

[0004]
(D) 50 ≦ Dyp / Dxp ≦ 180
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
AS: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxp: In the mercury intrusion method, in the pore distribution in the pore range of 0.001 to 0.1 μm, the mercury intrusion increase amount (integrated pore volume increase amount / log average pore diameter) is the maximum value (Dyp). Average pore diameter (μm)
Dyp: Maximum value of mercury intrusion increase (mg / l)
Dyp / Dxp: Average pore diameter The second aspect of the present invention is that calcium carbonate surface-treated with an organic surface treatment agent satisfies the following formulas (a), (b), (e) and (f): The content of the surface-treated calcium carbonate is as follows.
(A) 20 ≦ Sw ≦ 200 (m ² / g)
(B) 1.0 ≦ As ≦ 7.5 (mg / m ² )
(E) 0.03 ≦ Dxs ≦ 1 (μm)
(F) Dys ≦ 30 (wt%)
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
AS: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxs: Cumulative weight 5 calculated from the large particle side in the particle size distribution in the laser diffraction method (SALD-2000, manufactured by Shimadzu Corporation)

[0005]
0% average particle size (μm).
Dys: Cumulative weight (% by weight) of particle diameters exceeding 3 μm in the above particle size distribution
According to a third aspect of the present invention, the surface treated calcium carbonate is characterized by comprising calcium carbonate surface-treated with an organic surface treating agent and satisfying the following formulas (a) to (f).
(A) 20 ≦ Sw ≦ 200 (m ² / g)
(B) 1.0 ≦ As ≦ 7.5 (mg / m ² )
(C) 0.003 ≦ Dxp ≦ 0.03 (μm)
(D) 50 ≦ Dyp / Dxp ≦ 180
(E) 0.03 ≦ Dxs ≦ 1 (μm)
(F) Dys ≦ 30 (wt%)
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
As: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxp: In the mercury intrusion method, in the pore distribution in the pore range of 0.001 to 0.1 μm, the mercury intrusion increase amount (integrated pore volume increase amount / log average pore diameter) is the maximum value (Dyp). Average pore diameter (μm)
Dyp: Maximum value of mercury intrusion increase (mg / l)
Dyp / Dxp: Average pore diameter Dxs: 50% average particle diameter (μm) of cumulative weight from the large particle side in the particle size distribution in the laser diffraction method (manufactured by Shimadzu Corporation: SALD-2000).

[0007]
Although commercially available, the calcium carbonate forms tertiary particles in which secondary particles formed by aggregation of primary particles are further aggregated. Therefore, the surface treatment amount for covering calcium carbonate is 1.0 mg / Although the amount of treatment is less than m ² , the calcium carbonate of the present invention has less tertiary particle former than the conventional one, and the dispersibility of the secondary particle former is extremely high. Have difficulty. Therefore, when drying and pulverization are performed while the treatment amount is insufficient, tertiary agglomerates are formed between the untreated surfaces, so that the effect as the surface-treated calcium carbonate cannot be sufficiently exhibited. On the other hand, when it exceeds 7.5 mg / m ² , the surface treatment agent is liberated to the resin component or the plastic component due to the excess of the surface treatment agent, causing a bleed phenomenon and a rough surface phenomenon. Therefore, Preferably it is 1.5-5.0 mg / m < ² >, More preferably, it is 2.0-4.0 mg / m < ² >.
The heat loss per unit specific surface area is TG-8110 manufactured by Rigaku Corporation. About 100 mg of surface-treated calcium carbonate is sampled on a sample pan (made of platinum) having a diameter of 10 mm and heated at a rate of 15 ° C./min. The heat loss up to ° C. was measured to determine the heat loss rate (mg / g) per gram of surface-treated calcium carbonate, and this value was divided by the BET specific surface area value.
Equations (c) and (d) serve as indices for knowing the dispersion state of the surface-treated calcium carbonate of the present invention.
(C) is an average pore diameter (Dxp) of a value (Dyp) at which the amount of increase in mercury intrusion becomes maximum in the pore distribution in the range of 0.001 to 0.1 μm measured by the mercury intrusion method (porosimeter). It means the fineness of the gap between the surface treated calcium carbonate particles. Therefore, it represents the average diameter of the gaps between the primary particles, not the fineness of the particles shown by the (nitrogen) gas adsorption method of the formula (a), and it must be 0.003 to 0.03 μm. is there. If the average pore diameter is less than 0.003 μm, the primary particles

[0008]
In other words, the secondary particles are too fine, which causes a problem in stability over time. On the other hand, if it exceeds 0.03 μm, there are many secondary particle forming bodies in which the primary particles are too large or the primary particles are strongly agglomerated, and the high-viscosity physical property which is the object of the present invention is as follows. I can't get it. Therefore, it is preferably 0.005 to 0.025 μm, more preferably 0.006 to 0.020 μm.
The increase in the amount of mercury intrusion means the increase in the pore volume, and is expressed by the formula of (integrated pore volume increase / log average pore diameter) (unit: ml / g). As a matter of course, the smaller the pore diameter, the smaller the pore volume. Therefore, the maximum mercury intrusion increase (Dyp) depends on the pore diameter.
The formula (d) shows the number of average pore diameters of the formula (c), and is an index indicating the high viscosity that is the object of the present invention. As described above, the smaller the pore diameter, the smaller the pore volume. Therefore, it is necessary in the present invention by adding the maximum mercury intrusion increase amount (Dyp) and the average pore diameter (Dxp) of the formula (c). The amount (number) of pore diameters can be derived, and the higher the value of Dyp / Dxp, the higher the viscosity. Accordingly, it is necessary that the average pore diameter (Dyp / Dxp) of the present invention is 50 to 180. When Dyp / Dxp is less than 50, the high viscosity which is the object of the present invention cannot be obtained. On the other hand, if the average particle diameter exceeds 180, the average pore diameter is too small, which causes a problem in the temporal stability of the primary particles or secondary particles. Therefore, it is preferably 60 to 150, more preferably 70 to 130.
When the surface-treated calcium carbonate of the present invention is out of the ranges of the formulas (c) and (d), for example, the coating composition containing the calcium carbonate has low gloss, and the sealant composition has reduced strength at break. .
In addition, the mercury intrusion apparatus (porosimeter) used in the present invention and main measurement conditions are shown below.
<Measurement device>

[0010]
(I) Neutral detergent (5 times diluted with water) 2.0 g
(II) Calcium carbonate sample 0.4g
(III) Water 40g
In particular, it is preferable that the ultrasonic dispersion used as the pre-dispersion after adjusting with the above-described formulation as the pretreatment is performed under a certain condition, and the ultrasonic dispersion machine used in the examples of the present invention is US-300T (Nippon Seiki Seisakusho Co. And pre-dispersed under constant conditions of 100 μA-60 seconds. In addition, the neutral detergent is not particularly limited and is a general commercial product, and there is no problem.
In the particle size distribution measuring method described above, when the average particle diameter (Dxs) of the present invention is less than 0.03 μm, the temporal stability of the primary or secondary particles may be lowered. On the other hand, if it exceeds 1 μm, the number of tertiary particle forming bodies tends to increase as described above, and the dispersibility in the resin composition tends to deteriorate. Accordingly, the thickness is more preferably 0.05 to 0.8 μm, still more preferably 0.08 to 0.5 μm.
On the other hand, if the cumulative total weight (Dys) with an average particle diameter exceeding 3 μm exceeds 30% by weight, the dispersion state in the resin composition cannot be said to be sufficient, and it is difficult to obtain desired high viscosity properties. Therefore, it is more preferably 25% by weight or less, and most preferably 20% by weight or less.
When the surface-treated calcium carbonate of the present invention is out of the range of the above formulas (e) and (f), for example, the coating composition containing the calcium carbonate has reduced gloss, and the sealant composition has a breaking strength, etc. It is preferable that the surface-treated calcium carbonate of the present invention that easily causes problems further satisfy the following formulas (g) to (j). These define preferred ranges of the above-mentioned formulas (c), (d), (e), and (f), respectively.

[0016]
On the other hand, if it exceeds 15% by weight, the primary particles after the reaction are too fine, and the secondary particle size after aging may not satisfy the range of the formula (f) which is a preferable dispersion state. It is difficult to obtain a desired high viscosity. At the time of addition, either before the carbonation reaction or during the carbonation reaction, it may be added both before and during the reaction.
Complex forming substances include hydroxycarboxylic acids such as citric acid, oxalic acid and malic acid and alkali metal salts thereof, alkaline earth metal salts and ammonium salts; polyhydroxycarboxylic acids such as gluconic acid and tartaric acid and alkali metal salts thereof; Alkaline earth metal salts and ammonium salts; aminopolycarboxylic acids such as iminodiacetic acid, ethylenediaminetetraacetic acid, nitrilotriacetic acid and their alkali metal salts, alkaline earth metal salts and ammonium salts; polyphosphoric acids such as hexametaphosphoric acid and tripolyphosphoric acid and their alkalis Metal salts, alkaline earth metal salts and ammonium salts; ketones such as acetylacetone, methyl acetoacetate and allyl acetoacetate; sulfuric acid and alkali metal salts thereof, alkaline earth metal salts and ammonium salts, etc. Use in combination of two or more Possible it is. Of these, hydroxycarboxylic acids have high binding properties with calcium, and citric acid can be preferably used.
The carbon dioxide gas flow rate of (3) is usually 300 to 3000 L / hr per 1 kg of calcium hydroxide. If it is less than 300 L / hr, the primary particles after the reaction tend to be large, and if it exceeds 3000 L / hr, the cost is industrially increased.
Regarding the gas concentration of (4), 10 to 50% is preferable. When the gas concentration is less than 10%, the primary particles after the reaction tend to be large, and when it exceeds 50%, the cost is industrially increased.
(Maturation conditions)

[0020]
Examples of cationic surfactants include aliphatic amine salts such as stearylamine acetate and stearylamine hydrochloride, aliphatic quaternary ammonium salts such as lauryltrimethylammonium chloride and stearyltrimethylammonium chloride, and alkylbenzyldimethylammonium chloride. Cationic surfactants such as aromatic quaternary ammonium salts, heterocyclic quaternary ammonium compounds, amino groups (primary amine groups), imino groups (secondary amine groups), tertiary amine groups, quaternary ammonium groups, Cationic polymer dispersants having polar groups such as hydrazino groups, monomers copolymerizable with monomers having these polar groups, such as α, β unsaturated monocarboxylic acids, α, β unsaturated dicarboxylic acids Acids, alkyl methacrylates, (meth) alkoxy groups Ryl ether, (meth) acrylate having cyclohexyl group, α, β monoethylenically unsaturated hydroxy ester, polyalkylene glycol mono (meth) acrylate, vinyl ester, vinyl aromatic, unsaturated nitrile, unsaturated dicarboxylic acid ester, vinyl ether , Copolymers with monomers such as conjugated dienes, chained olefins, cyclic olefins, sulfo group-containing monomers, and salts partially or completely neutralized by alkali metals, alkaline earth metals, ammonium, etc. Is given as an example.
Furthermore, examples of nonionic surfactants include betaine, aminocarboxylic acid, and imidazoline derivatives exemplified by polyoxyethylene and derivatives thereof, carboxybetaine, sulfobetaine and the like.
After the surface treatment, it is preferable to filter and wash contaminated ions such as alkali metal ions contained in the slurry so as to satisfy the above-described formula (l). The electrical conductivity of the filtrate is not particularly limited, but is usually 10 mS / cm or less, more preferably 1 mS / cm or less, and even more preferably 300 μS / cm.

[0022]
Resin for solvent-based paints typified by fluorine resin, styrene resin, melamine resin, epoxy resin, and water-based paint, alkyd resin, acrylic resin, latex resin, vinyl acetate resin, urethane resin, silicone resin, fluorine resin, Emulsion resins for general paints typified by styrene resins, melamine resins, epoxy resins, etc. Water-soluble resins for general paints, emulsion resins typified by alkyd resins, amine resins, styrene-allyl alcohol resins, aminoalkyd resins, polybutadiene resins, etc. Dispersion resins for paints that are blended with water-soluble resins, dispersion resins that use cross-linked water-soluble resins as emulsifiers, acrylic hydrosols, etc., and these resin components can be used alone or in combination of two or more Is done.
The blending ratio of the surface-treated calcium carbonate of the present invention and these resins is not particularly limited, and may be appropriately determined according to desired physical properties. Usually, the surface-treated calcium carbonate is 1 to 100 parts per 100 parts by weight of the resin. Part by weight is preferred. Of course, various additives such as a plasticizer and a dispersant may be added as necessary.
Examples of the plastisol resin include vinyl chloride sol, acrylic sol, water-soluble acrylic sol, and urethane sol. These resin components are used alone or in combination of two or more.
The blending ratio of the surface-treated calcium carbonate of the present invention and these resins is not particularly limited, and may be appropriately determined according to desired physical properties. Usually, the surface-treated calcium carbonate is 1 to 100 parts per 100 parts by weight of the resin. Part by weight is preferred. Of course, various additives such as a stabilizer may be added as necessary.
The resin for ink is not particularly limited, but rosin modified phenolic resin, urea resin, melamine resin, ketone resin, polyvinyl chloride

[0041]

Claims (17)

A surface-treated calcium carbonate comprising calcium carbonate surface-treated with an organic surface treating agent and satisfying the following formulas (a), (b), (c) and (d):
(A) 20 ≦ Sw ≦ 200 (m ² / g)
(B) 1.0 ≦ As ≦ 7.5 (mg / m ² )
(C) 0.003 ≦ Dxp ≦ 0.03 (μm)
(D) 50 ≦ Dyp / Dxp ≦ 180
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
As: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxp: In the mercury intrusion method, in the pore distribution in the pore range of 0.001 to 0.1 μm, the mercury intrusion increase amount (integrated pore volume increase amount / log average pore diameter) is the maximum value (Dys). Average pore diameter (μm)
Dyp: Maximum value of mercury intrusion increase (mg / l)
Dyp / Dxp: average pore size A surface-treated calcium carbonate, wherein the calcium carbonate surface-treated with an organic surface treatment agent satisfies the following formulas (a), (b), (e) and (f):
(A) 20 ≦ Sw ≦ 200 (m ² / g)
(B) 1.0 ≦ As ≦ 7.5 (mg / m ² )
(E) 0.03 ≦ Dxs ≦ 1 (μm)
(F) Dys ≦ 30 (wt%)
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
As: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxs: 50% cumulative particle weight average particle diameter (μm) calculated from the large particle side in the particle size distribution in the laser diffraction type (manufactured by Shimadzu Corporation: SALD-2000).
Dys: Cumulative weight (% by weight) of particle diameters exceeding 3 μm in the above particle size distribution A surface-treated calcium carbonate comprising calcium carbonate surface-treated with an organic surface treating agent and satisfying the following formulas (a) to (f):
(A) 20 ≦ Sw ≦ 200 (m ² / g)
(B) 1.0 ≦ As ≦ 7.5 (mg / m ² )
(C) 0.003 ≦ Dxp ≦ 0.03 (μm)
(D) 50 ≦ Dyp / Dxp ≦ 180
(E) 0.03 ≦ Dxs ≦ 1 (μm)
(F) Dys ≦ 30 (wt%)
However,
Sw: BET specific surface area by nitrogen adsorption method (m ² / g)
As: Heat loss per unit specific surface area calculated by the following formula (mg / m ² ) (mg / g heat loss per gram of surface-treated calcium carbonate at 200 ° C. to 500 ° C.) / Sw
Dxp: In the mercury intrusion method, in the pore distribution in the pore range of 0.001 to 0.1 μm, the mercury intrusion increase amount (integrated pore volume increase amount / log average pore diameter) is the maximum value (Dys). Average pore diameter (μm)
Dyp: Maximum value of mercury intrusion increase (mg / l)
Dyp / Dxp: Average pore diameter Dxs: 50% average particle diameter (μm) of cumulative weight from the large particle side in the particle size distribution in the laser diffraction method (manufactured by Shimadzu Corporation: SALD-2000).
Dys: Cumulative weight (% by weight) of particle diameters exceeding 3 μm in the above particle size distribution The surface-treated calcium carbonate according to any one of claims 1 to 3, wherein the calcium carbonate surface-treated with the organic surface treatment agent satisfies the following formulas (g) to (j).
(G) 0.005 ≦ Dxp ≦ 0.025 (μm)
(H) 60 ≦ Dyp / Dxp ≦ 150
(I) 0.05 ≦ Dxs ≦ 0.8 (μm)
(J) Dys ≦ 25 (% by weight) The surface-treated calcium carbonate according to any one of claims 1 to 4, wherein the calcium carbonate surface-treated with the organic surface treatment agent satisfies the following formula (k).
(K) 0.1 ≦ Sw · Dxp ≦ 1.5 The surface-treated calcium carbonate according to any one of claims 1 to 5, wherein the alkali metal salt contained in the calcium carbonate surface-treated with the organic surface treatment agent satisfies the following formula (1).
(L) 0.03 ≦ Is ≦ 3 (μmol / m ² )
However,
Is: Alkali metal content per unit specific surface area calculated by the following formula {metal content per 1 g of calcium carbonate (mmol / g)} / Sw (m ² / g) The surface-treated calcium carbonate according to any one of claims 1 to 6, wherein the calcium carbonate slurry before the surface treatment with the organic surface treatment agent (after aging) satisfies the following formula (m).
(M) 0.03 ≦ Dx ≦ 0.40 (μm)
However,
Dx: Particle size (μm) at 50% cumulative weight calculated from the large particle size side in the particle size distribution measured by centrifugal particle size distribution analyzer (manufactured by Shimadzu Corporation: SA-CP4) Organic surface treatment agent is saturated fatty acid, unsaturated fatty acid, resin acid, sulfonic acid, their alkali metal salt, alkaline earth metal salt, ammonium salt, amine salt, cationic surfactant, anionic surfactant, and The surface-treated calcium carbonate according to any one of claims 1 to 7, wherein the surface-treated calcium carbonate is at least one selected from nonionic surfactants. 0.5-15% by weight of a substance that forms a complex by coordinating with metal ions is added to the calcium hydroxide slurry, carbon dioxide is blown to synthesize calcium carbonate by a carbonation reaction, and the calcium carbonate concentration is set to 2 A method for producing surface-treated calcium carbonate, characterized by adjusting and aging to 4 to 13.0% by weight, and surface-treating the obtained calcium carbonate with an organic surface treatment agent. A resin composition comprising the surface-treated calcium carbonate according to any one of claims 1 to 8 blended with a resin. The resin composition according to claim 10, wherein the resin is a molding resin. The resin composition according to claim 10, wherein the resin is a paint resin. The resin composition according to claim 10, wherein the resin is a plastisol resin. The resin composition according to claim 10, wherein the resin is an ink resin. The resin composition according to claim 10, wherein the resin is a sealant resin. The resin composition according to claim 10, wherein the resin is an adhesive resin. The compounding quantity of surface treatment calcium carbonate is 1-100 weight part with respect to 100 weight part of resin, The resin composition of any one of Claims 10-16.